An April 2019 UK study 1 looked at the sort of food, drink and lifestyle choices made by meat-eaters and plant-eaters to see if differences in health outcomes of the two groups were partly the result of these choices.
The researchers analysed data from FFQs (food frequency questionnaires) completed by 30,239 participants involved in the EPIC-Oxford study 2 . They assessed intakes of major protein-source foods and other food groups after dividing the participants into six groups of meat-eaters and non-meat-eaters:
The foods listed in the FFQs were categorised into 45 food groups and the results were analysed for variance in health outcomes between the 6 groups. Figures 1 (men) and 2 (women) give a rough idea of the results:
There are large differences in dietary intakes between meat-eaters and non-meat-eaters:
non-meat-eaters consumed higher amounts of:
nuts and seeds
vegetables and fruits
non-meat-eaters consumed lower amounts of:
sugar-sweetened beverages (SSBs)
other foods high in free sugars (e.g. ice cream)
Contrary to expectations, vegetarians and vegans did not replace meat with higher intakes of animal-sourced protein alternatives (dairy and eggs) and non-animal protein alternatives (including legumes and nuts), respectively.
Vegetarians and vegans were found not to completely replace meat consumption with non-meat protein sources and high protein plant-sources but, rather, they increased their consumption of a large variety of plant-based foods and consumed lower amounts of high protein-sourced foods compared with meat-eaters.
The positive health benefits of lower protein intake (specifically, animal protein) have been discussed previously 3456 .
The proportion of total energy from high protein-sourced foods:
regular meat-eaters – 33%
vegetarians – 25%
vegans – 20%
Compared with the 5 other groups, vegans consumed the highest amount of:
lower amount of dairy and eggs than meat-eaters
highest amount of cheese compared with other 5 groups
Egg consumption was low in all 6 groups, possibly because this study looked at a cohort that might be more ‘health conscious’ than the rest of the population. 7
Compared with regular meat-eaters, all the other groups:
had a higher education level
had a lower socio-economic status
were less likely to smoke and consume alcohol
had higher levels of physical activity
had lower BMI
had higher intakes of carbohydrates
had lower intakes of protein and fat
Table 1 shows more detail on the above:
The findings suggest that non-meat-eaters might be consuming an overall “healthier” diet than meat-eaters.
“In this large study of British men and women, we compared intakes of major protein-source foods and other food groups. …Our results show that meat-eaters and low and non-meat-eaters do not only differ in their meat consumption but in their overall dietary intake…The dietary intakes consumed by low and non-meat-eaters might explain the lower risk for some diseases in these diet groups and can be used as a real-life guide for future work assessing the health impacts of replacing meat intake with plant-based foods or dietary recommendations.”
On the whole, the results are what one would have expected. However, there were some surprises, particularly the findings that non-meat eaters tend to drink less booze, smoke less, and eat less processed and sweetened foods.
It’s often speculated, by those who are unfamiliar with plant-based diets, that life must be more boring when you stop eating animals – I mean, where’s the fun in eating grass?! However, if life were so dull when eating a supposedly buzz-free diet, wouldn’t you imagine that plant-eaters would eat a lot more comfort food 8 (sugary, fried, processed foods) and drink and/or smoke themselves silly whenever they could?
Some clarification is provided by research data showing that, not only does physical health generally improve on a plant-based diet, but mental health 91011 and general outlook on life 12 also tends to improve – obviating the need to get caught in that “pleasure trap” 13 .
It was also interesting to note from this study, that the improved health outcomes for plant-eaters does not just derive from the fact that they eat more healthy foods – it’s also that they generally appear to eat less unhealthy food, exercise more, smoke and drink less. There was also variance by age, socio-economic and educational status between the groups – with the youngest group being vegan, highest socio-economic status being meat-eaters, and the most educated being fish-eaters. Food for thought…
Of course, this is not to say that there are no vegetarians and vegans eating horrendously unhealthy plant-based diets. This is something that’s been covered in previous blogs 141516 . This can probably be seen by the surprisingly low amount of fruit and veg eaten by vegetarians and vegans, when compared with how much rice, pasta and bread they eat.
Since WFPB (especially when non-SOS) would guarantee a maximum amount of fruit and veg, with a minimum amount of the sort of junk foods that can find themselves included in a vegetarian or vegan diet, it would be interesting to see future studies which are able to include the WFPB diet within a list of food groups.
A 2019 Taiwanese study 1 recently reported on the results of two large-scale cohort studies which were analysed in order to establish whether following a vegetarian diet reduces the risk of developing gout, when compared with following a non-vegetarian diet.
What is gout?
This subject has been covered extensively in a previous blog 2 so, in brief terms:
gout is the most common inflammatory joint disease and is an important risk factor for hypertension, diabetes, kidney diseases, cardiovascular diseases, and all-cause and cardiovascular mortality 3456
gout pathogenesis begins with excess serum urate that forms monosodium urate crystals – a salt or ester of uric acid – in the joints, triggering gouty inflammation and resulting in excruciating pain 78
cases of gout have doubled or tripled in many countries in the past decades 910 making it a serious public health threat which desperately requires preventive strategies
Taiwan is particularly affected, with one of the highest incidences and prevalences of gout in the world 11
Two cohort groups, representing almost 14,000 Taiwanese, were followed for between 7 and 9 years. They were divided into vegetarians (n=4684) and non-vegetarians (n=9251), and appropriate tests were undertaken to establish gout occurrence.
the standard therapeutic diet aimed at preventing/managing gout restricts purine intake which is metabolised into urate and contributes to one-third of the body’s total urate pool 12
however, purine exclusion diets have only moderate urate-lowering effects and are generally regarded as an insufficient remedy 13
the researchers considered that the ideal diet for gout prevention/management should be able to simultaneously reduce uric acid and inflammation, while preventing gout-associated comorbidities
they conjectured that a vegetarian diet may be a promising dietary pattern to target multiple pathways in the gout pathogenesis, since:
vegetarians avoid purine-rich meat/seafood, while consuming increased amounts of vegetables, whole grains, seeds and nuts 1415
plant foods contain polyphenols which potentially reduce uric acid via both an inhibition of xanthine oxidase16 activities and the enhancement of uric acid excretion 17
plant foods contain phytochemicals which potentially attenuate the NLRP3 18 inflammatory pathway 1920
vegetarian diets have already been shown to reduce gout associated comorbidities, such as cardiovascular diseases 21 , diabetes 2223 , and hypertension 2425
“In these two prospective cohort studies, a Taiwanese vegetarian diet is associated with lower risk of gout. This association persists after controlling for demographic, lifestyle, cardiometabolic risk factors, and baseline hyperuricemia. This finding does not differ across subgroups of sex, lifestyle factors, or comorbidities.”
it’s most likely that vegetarians experienced a lower risk of gout simply because they had lower uric acid levels since their diets avoid purine-rich meat and seafood – a diet which in prospective studies has been shown to increase gout incidence and recurrence26272829
the results appear to go beyond the single effects of uric acid levels, since they were not consistently wide apart between all vegetarians and all non-vegetarians. The other potential factors influencing the reduction of gout in vegetarians may also be accounted for by the following:
vegetarian diets have higher alkalinity which has been shown to facilitate more effective uric acid excretion than an acidic diet – i.e. one that is fish/meat-based 30
vegetarian diets usually contain lower saturated fat, higher unsaturated fat and phytochemical-rich plant foods 141531
the latter may prevent inflammatory responses which trigger gout attacks by dampening the inflammatory activation of NLRP3 inflammasome 32
fibre (high in plant-based diets) on its own, and when metabolised into short chain fatty acids by gut microbiota, has been shown to resolve inflammatory responses involved in gout attacks in mice 33 and in humans 34
We saw in the previous gout blog 2 that there’s plenty of strong evidence to suggest that the best possible dietary option for gout-avoidance is a WFPB diet (with zero alcohol!). Of course, any diet which favours plant over animal foods will be of some benefit, and the more the latter is replaced with the former, the better in terms of gout-avoidance.
One interesting finding from this Taiwanese study relates to soy. Taiwanese vegetarian diets replace meat and seafood with soy products. But there appears to be a paradox here. Soy has a high purine content and has attracted an infamous reputation – even amongst health professionals – for causing gout 35 . However, contrary to this widely-held belief, the vegetarian diets with high soy content covered in this present Taiwanese study appear to lower gout risk.
And this is not the only study to show this. The researchers’ findings are consistent with the “Singapore Chinese Health Study” which found that soy was protective toward gout 27 .
A potential explanation for this rests in the fact that the potential of soy purines – mainly adenosine36 and guanine37 – to raise uric acid levels is considerably lower than those in meat and fish, which have a higher proportion of their purines in the form of hypoxanthine383940
A 2012 prospective study 41 of gout patients found that the impact of plant purine on gout attacks was significantly less than the purine from animal sources.
Finally, research suggests 42 that soy may have the ability to prevent gout through the inhibition of both the above-mentioned NLRP3 inflammatory pathway and the activity of the caspase-1 enzyme. The latter is an essential effector of inflammation, pyroptosis43 , and septic shock44 .
So, hurrah for the plants, boo hiss for meat and seafood, and don’t be shy about eating soy…
Xanthine oxidase is a type of enzyme that generates reactive oxygen species. These enzymes catalyse the oxidation of hypoxanthine to xanthine and can further catalyse the oxidation of xanthine to uric acid. [↩]
Adenosine is a chemical that is present in all human cells. It readily combines with phosphate to form various chemical compounds including adenosine monophosphate (AMP) and adenosine triphosphate (ATP). [↩]
Guanine is one of the four main nucleobases found in the nucleic acids DNA and RNA, the others being adenine, cytosine, and thymine. [↩]
Hypoxanthine is a naturally occurring purine derivative. It is occasionally found as a constituent of nucleic acids, where it is present in the anticodon of tRNA in the form of its nucleoside inosine. [↩]
(Pyroptosis is a highly inflammatory form of programmed cell death that occurs most frequently upon infection with intracellular pathogens and is likely to form part of the antimicrobial response. [↩]
Septic shock is a potentially fatal medical condition that occurs when sepsis, which is organ injury or damage in response to infection, leads to dangerously low blood pressure and abnormalities in cellular metabolism. [↩]
Asthma is a respiratory condition characterised by spasms in the bronchi of the lungs, resulting in breathing difficulties. It’s normally associated with allergic reactions or other forms of hypersensitivity. This blog will take a brief look at some evidence that suggests a central role for plant-based diets in the treatment of asthma and the prevention of asthmatic attacks.
Healthy body weight and asthma
two 2013 studies on asthma in children found that being overweight increases the risk of developing asthma by 35%, while being obese as a child increases the risk by 50% 1 and losing excess weight in children improves lung function2
this was further supported by a 2018 study: ““There are few preventable risk factors to reduce the incidence of asthma but our data show that reducing the onset of childhood obesity could significantly lower the public health burden of asthma.” 3
Fatty acid intake and asthma
Omega-6 fatty acids are mostly found in animal products. They are also found in margarines and other vegetable oils. The specific amounts of oil-based fats are shown in the chart below 4 . N.B. Consuming any form of oil or fat that’s been separated from its original food source is not to be advised, for reasons covered in previous blogs. 567 .
arachidonic acid (a long-chain omega-6 fatty acid) is found mainly in animal foods and has been shown to be a precursor of leukotrienes which have bronchoconstrictive effects 8 . Leukotrienes are a form of pro-inflammatory molecule released by mast cells during asthma attacks 9
omega-3 fatty acids, on the other hand, have been shown 10 to have anti-inflammatory effects
a higher ratio of omega-6 to omega-3 fatty acids in the diets of children has been shown 10 to have a significant association with an increased risk of asthma
omega-6 fatty acids have been shown 11 to hinder the incorporation of omega-3 fatty acids into tissue lipids and plasma
while some studies suggest 12 that fish-based omega-3 intake improves asthma symptoms in children, there are other studies 13 which contradict this and also suggest that such benefits in adults have not been proven
there are persuasive reasons for getting your omega-3 from walnuts, flaxseeds/chia seeds and/or plant-based omega-3 supplements rather than eating fish or using fish oil supplements 1415
Saturated fat and asthma
evidence suggests 16 that when asthmatics eat diets containing high levels of total and saturated fat, there is an increase in the expression of those genes involved in airway inflammation
a 2010 study concluded 17 that high fat diets are able to inhibit the asthmatic’s response to the asthma medication Ventolin (albuterol)
Dairy products and asthma
a study 18 showed that pregnant women consuming low-fat yogurt once or more a day or low-fat milk 5.5 times or more a week had a 21% and 8% higher risk, respectively, for having a baby which would be diagnosed with asthma, as compared with women consuming no dairy
a 2015 study 19 found roughly 50% greater asthma prevalence in children who consumed butter 3 or more times a week, compared with those who either never consumed butter or only consumed it occasionally
Fast food and asthma
a 2013 study 20 found a ~40% increased risk of severe asthma developing in children and adolescents who consumed fast food 3 or more times a week, as compared with those who either never ate fast food or ate it only occasionally
Nuts, seeds and asthma
although tree nuts and peanuts can be allergenic to some people, a 2012 Danish study 21 found that nut intake during pregnancy was actually inversely related to an asthma diagnosis in their offspring at 18 months of age
a 2009 French study 22 looked at the risk that French women have of frequent asthma attacks (1 or more per week), and found that the risk was lower in women who consumed the highest amount of nuts and seeds (>5.3 g/day) when compared with those with the lowest consumption (≤ 1.0 g/day)
Salt and asthma
whilst there is evidence 23 that consuming a low-sodium (salt) diet appears to reduce bronchoconstriction in asthmatics in response to exercise, there is no strong evidence that a low-sodium diet (of itself) reduces the prevalence or severity of asthma 24
considering that salt is known 25 to be pro-inflammatory, it makes sense that it’s wise to avoid adding salt to your food and, of course, avoiding procesed foods which are known to be high in salt
a 2014 study concluded: “…our findings suggest that higher sodium consumption is associated with greater adiposity, leptin resistance, and inflammation independent of total energy intake and sugar-sweetened soft drink consumption.” 26
Fruits, vegetables and asthma
fruits, vegetables and other foods high in antioxidants have been shown 27 to produce ~45% lower risk for asthma in those children and adults who consume the most amount of fruits and vegetables, as compared with those who eat the least amount
a 2013 study 28 found that individuals who ate the lowest amount of fruit and vegetable (3 servings/day – typical of Western diets) had more than 50% increased risk of asthma exacerbation than those who ate 7 daily servings of fruits and vegetables
the European Academy of Allergy and Clinical Immunology (EAACI) recommended that clinical advice should be to increase the net intake of fruits and vegetables as a way of reducing the risk of asthma, particularly in children 29
a 2017 study concluded “higher intakes of fruits and vegetables may have a positive impact on asthma risk and asthma control.” 30 and provided an interesting schematic that compared the airway effects of the Western diet and a diet high in fruit and veg:
Vegetarian, vegan diets and asthma
a 1994 study 31 of almost 28,000 Seventh-day Adventists found that vegetarian women amongst the group reported a lower incidence of asthma, as compared to women who ate omnivore diets. “The theoretical basis for the value of vegan diets is the absence of potential triggers, particularly dairy products and eggs, as well as a relative lack of arachidonic acid.” 32
although the so-called Mediterranean diet is something of an anathema these days – with the spread of the modern Western diet across the continent – a 2014 review 33 found 7 out of 10 studies noted that there was a protective effect of a Mediterranean diet on the incidence of child asthma
a 1985 study used a vegan diet for 1 year as an alternative therapy to typical asthma drugs for a group of 35 asthma patients. They found a significant decrease in asthma symptoms as a result of this simple dietary intervention: “…71% reported improvement at 4 months and 92% at 1 yr. There was a significant improvement in a number of clinical variables; for example, vital capacity, forced expiratory volume at one sec and physical working capacity, as well as a significant change in various biochemical indices as haptoglobin, IgM, IgE, cholesterol, and triglycerides in blood. Selected patients, with a fear of side-effects of medication, who are interested in alternative health care, might get well and replace conventional medication with this regimen.” 34
Sugar-sweetened beverages and asthma
a 2009 US study 35 found an increased risk of developing asthma in those students who drank soda (fizzy drinks): 2 regular sodas a day meant a 28% increased risk, while 3 or more regular sodas a day meant a 64% increased risk. It was also pointed out that previous studies found asthma symptoms were worsened by regular soda consumption
a follow-up study 36 on non-obese adults found that those who consumed 2 or more sugar-sweetened beverages a day had ~65% increased risk of developing asthma, as compared to those who didn’t consume any such beverages
and it’s not just sodas that are the problem – a further 2016 US study 37 found that asthma risk in children between 2 and 9 years of age was significantly higher when they consumed apple juice or high fructose corn syrup-sweetened beverages 5 or more times a week, as compared to consuming only 1 or no such beverages per month
Alcohol and asthma
a 2012 study 38 found a U-shaped association between alcohol consumption and the development of new onset asthma in adults – that is, moderate weekly intake (1-6 units/week) showed a reduced risk, whilst those who never/rarely drank (<1 unit/month) and heavy drinkers (≥4 units/day) showed an increased risk. The risk of new-onset asthma was also shown to be lower for subjects with wine preference when compared with beer preference. However, the study authors admit that their findings were not statistically significant
contradictory information is provided by other authorities, including Asthma UK 39 , which claims that alcohol does exacerbate asthma symptoms, and a study in The Journal of Allergy and Clinical Immunology 40 , which states that wines are the greatest triggers for asthma attacks
whilst there’s obviously disagreement on this subject, and thus further research would be useful, previous blogs 4142 have explained the reasons why any amount of alcohol intake has been shown to be potentially harmful
Vitamin D status and asthma
a 2014 meta-analysis 43 found that increased vitamin D deficiency was associated both with an increase in the incidence of asthma in general and with a decrease in lung function in asthmatic children in particular
whilst there is some disagreement on the benefits of vitamin D supplementation as a means of treating/preventing asthma in children 44 , an additional study 45 reported that those children who took vitamin D supplements reduced their risk of asthma by ~25%, as compared with children without supplemental vitamin D
Breastfeeding and asthma
a 2004 study 46 on the therapeutic measures for preventing the development of both allergic rhinitis and asthma, made the following suggestions for decreasing the the risk for developing asthma in babies during breastfeeding:
ensure that babies are breastfed for the first 4-6 months of life
avoid dairy products until at least 1 year old
avoid eggs until at least 2 years old
avoid nuts and fish until at least 3 years old
Inhalers and asthma
An interesting article appeared in The Telegraph today 47 entitled “Asthma inhalers as bad for the environment as 180-mile car journey, health chiefs say.” It points out the dangers to the environment of the hydrofluorocarbons (a powerful greenhouse gas) contained in the majority of the asthma inhalers (known as metered dose inhalers of MDI’s) used in the UK.
Nice (The National Institute for Health and Care Excellence) was reported to have calculated that “…five doses from an MDI have the same carbon emissions as a nine-mile trip in a typical car. The devices usually contain 100 doses. By contrast, dry powder inhalers are only around one fifth as bad for the environment.”
more than 5.4 million people in the UK receive treatment for asthma, including 1.1 million children
Britain has some of the highest rates in Europe, with around three people a day dying as a result of the condition
Whilst inhalers do, of course, save lives and users should only consider making changes in consultation with their doctor, they are known 48 to have side effects. Making dietary changes that help to prevent and treat asthma does seem to be a much better alternative, especially since the only side effects appear to be positive ones.
The foregoing appears to suggest that there is, indeed, an important role for plant-based diets in the prevention and treatment of asthma. Such diets (so long as they are based on wholefood plants and avoid processed plant foods) are excellent for the maintenance of healthy weight and can provide the ideal fatty acid profile.
It’s clear that some particular foods are best avoided completely, including dairy products, fast food, sugar-sweetened beverages and, arguably, excessive amounts of salt – especially when contained in processed foods.
If you suffer from asthma, perhaps a useful way to check whether this dietary approach will alleviate your asthma is to stick with your current diet for a specific time, but keep a detailed daily record of asthma symptoms. After this, change to a non-SOS WFPB (no added sugar, salt or oil wholefood plant-based diet) for a similar specific period of time and maintain the daily diary. You would then be able to compare the frequency and intensity of symptoms between the two periods.
Should you decide to do this, and would like to share the results, please feel free to write to me with your findings and I will aim to publish them in a subsequent blog.
In previous blogs, I shared two documentary films produced by the H.O.P.E. project 1 : “What You Eat Matters” 2 and “From Cancer Patient to Plant-Based Strong Man” 3 . H.O.P.E. have just released another short documentary film about Paul Chatlin, a man with heart disease who was saved from surgery by changing to a plant-based diet.
Paul Chatlin’s Story
In 2013, after being diagnosed with heart disease, Paul’s doctor gave him a simple choice – change his diet or undergo major heart surgery.
At the time, Paul was eating a typical Western diet, with cheese and meat being his favourite foods. Having loved pretty much anything fried in oil, he was given a “nutrition prescription” which required him to give up all these foods and cut out the oil – replacing his habitual diet with a low fat, whole food, plant-based diet.
Having spent his whole life eating one way, he found it a struggle to know what he could now eat and how he could prepare it without using oil. Luckily, he came across and attended a seminar on plant-based nutrition by the world-renowned physician and researcher Dr. Caldwell B. Esselstyn 4, a major player in the famous WFPB documentary film, “Forks Over Knives” 5 and author of his must-read book, “Prevent and Reverse Heart Disease: The Revolutionary, Scientifically Proven, Nutrition-Based Cure.” 6 .
As a result of the seminar, Paul was better equipped and motivated to strike out with his new diet and lifestyle. One month on, his heart pain went away completely. Within a year, his cholesterol levels had dropped from 309 to 122. He also lost over 40 lbs (18 kg).
Paul was so amazed with the health impacts of changing to a plant-based diet, that he started The Plant Based Nutrition Support Group (PBNSG) 7 to help others make the transition to the optimally health WFPB diet.
In this second in the series of H.O.P.E. ‘Plant Power Stories’, Paul shares his journey back to health and encourages us all to give back to our communities.
If you consider that plant-based eating is of value to the health and well-being of your friends and family, perhaps you could consider sharing this blog with them.
So many people are facing a lifetime on medications and/or having invasive surgery for conditions that could be avoided and treated with simple dietary changes. But, of course, they have to know that such an alternative exists in the first place!
Whilst anecdotal success stories such as Paul’s are likely to inspire hope, all nutritional claims made on this website are always backed up by peer-reviewed, scientific research.
Diverticulitis is a very unpleasant and potentially lethal condition which is increasingly afflicting populations eating the modern Western diet. This blog will look in some detail at its symptoms, causes and history, as well as potential ways in which you can avoid allowing this often hidden-until-too-late condition to creep up on you.
N.B. THIS BLOG CONTAINS SOME GRAPHIC IMAGES.
What are the symptoms of diverticulitis?
The really dangerous thing about this disease is that there can be no symptoms at all until you drop dead. Indeed, it’s reported 1 that nine out of ten people who die of diverticulitis did so without ever even knowing they had it!
Although it can be an asymptomatic disease, there are a range of symptoms that may appear 23 , including:
abdominal pain, normally on the left side (ranging from slight to excruciating)
The clue is in the word itself – the Latin word dīverticulum means turn aside or divert. This diversion is exactly what can happen to some of the food (called chyme) as it passes through the intestines (usually in the colon – also known as the bowel), the muscular walls of which are “diverted” outwards into the abdomen. Peristalsis is a process where the muscles of the intestinal walls contract and relax so that the chyme gradually gets pushed along to the anus and out of the body.
If weak spots are formed in the outer layer of the intestinal wall, the muscles can push outwards laterally, forming pouches or diverticula (diverticulosis). Although the plural is “diverticuli”, many authorities still use “diverticula” for singular and plural. These diverticula can then become inflamed, infected, and start bleeding (diverticulitis). The greatest danger is that infected diverticula will eventually burst, seeping intestinal contents into the bloodstream. This can lead to sudden death.
It’s obvious, then, that diverticulosis occurs first. This condition is usually completely unnoticed and most people never know they have it unless it’s found on a routine colonoscopy. Diverticulitis comes next, and it’s the reason people end up in hospital. It’s reported that 10-25% of individuals with diverticular disease end up developing symptoms such as abdominal pain, bloating, irregular bowel movements, bleeding, or signs of infection. 67
Doctors often use the analogy of an over-inflated inner tube poking out through the wall of a tyre. Similarly, increased internal pressure can force the gut to balloon out through weak spots in the intestinal wall. The results are pretty obvious and rather unpleasant:
If the pressure builds up so much and the diverticula rupture, intestinal contents can be pushed into the abdomen and end up in the blood stream. 8
The reason internal pressure can increase so much within the intestines (usually in the colon) is related to the type and quantity of food (chyme) that’s passing through. Continuing the inner tube for intestine analogy – imagine your fingers doing the peristalsis movement and squeezing along a lump of soft mashed potato inside the tube. Should be pretty easy. However, replace the mashed potato with thick gooey molasses and it would be much harder to squeeze it along, resulting in increased internal pressure. If, over a long period of time, your colon is having to squeeze small and compacted lumps, rather than gently contract and dilate around large and soft lumps, damage is pretty inevitable. 9
Most diverticula are not particularly large – around 1-2 centimetres in diameter – but, nevertheless, even at this size they can be big enough to cause symptoms and complications in some people. 10
Dietary fibre & diverticulitis
Just as in the previous blog on constipation 11 , it comes down to the amount of fibre in your diet – too little, and our faeces become small and firm. The same thing is happening within our intestines. If there’s not enough ‘bulk’, the intestines have to squeeze really hard to move the chyme along, and this pressure buildup can force out those bulges and eventually lead to the colon literally rupturing itself.
High-fibre diets make for larger and easier movements through the colon. Plant-based diets contribute a considerable range of intestinal health benefits: adding huge amounts of natural prebiotics and probiotics that permit the gut bacteria (the microbiome) to do their magic: providing anti-inflammatory, anti-cancer, anti-obesity and blood sugar control effects; reducing the risk of stroke, high cholesterol and heart disease; helping to prevent hiatal hernia, brain loss, kidney stones, COPD, Parkinson’s disease, and diabetes; aiding weight loss; improving immunity, and ultimately increasing healthy longevity 12 . That our bodies are able to produce sufficient nitric oxide (a powerful antioxidant) is another factor that is of vital importance to the maintenance of health; and, as previous blogs have considered 1314 , the quality and quantity of plant foods within our diet dictates the type of microbiome inhabiting all parts of our bodies – from our mouths and intestines to our bladder.
I came across a nice Australian site which stated the following: “We evolved in tandem with our gut microbiome, the bacteria and other microbes that inhabit our gut. They are just as much a part of our digestive system as our own cells. They feed on dietary components that are not absorbed in the small intestine, such as dietary fibre and resistant starch. The microbiome pays its fare by providing us with energy and nutrients that would otherwise have been lost. The large bowel or colon is essentially a fermentation vat. This explains the gas.” 15 It’s always good to see that on the other side of the planet, these WFPB websites are quoting the likes of Drs McDougall, Greger, Popper and Klaper.
Low-fibre diets are not the only risk factor for diverticulitis. Additional contributing factors include smoking, being obese, and eating a diet which is high in red meat and animal fat. One study on meat intake and risk of diverticulitis in men, concluded: “Red meat intake, particularly unprocessed red meat, was associated with an increased risk of diverticulitis.” 16
This is backed up by a 2017 study:
“During 894,468 person years of follow-up, we identified 1063 incident cases of diverticulitis….The association between dietary patterns and diverticulitis was predominantly attributable to intake of fiber and red meat.” 17
The modern Western diet contains high levels of animal-based and processed foods. Whilst it’s obvious that animal foods are completely devoid of fibre, some people need to be gently reminded that most processed foods are also very fibre-poor, with most fibre being stripped out during the manufacturing process. 18
Medical advice should always be sought if you have any symptoms of diverticulitis. Most diagnoses are during an acute attack of abdominal pain.
Your doctor will normally want to give you a physical examination (checking abdominal tenderness) in order to establish the cause of the pain – and there can be a wide range of causes other than diverticulitis.
Women would also normally have a pelvic examination to rule out pelvic disease. After this, the following are possible diagnostic tests:
blood and urine tests (checking for signs of infection)
pregnancy test for women of childbearing age (ruling out pregnancy as a cause of abdominal pain)
liver enzyme test (ruling out liver-related causes of abdominal pain)
stool test (ruling out infection in patients with diarrhoea)
CT scan (identifying inflamed/infected pouches and to confirm a diagnosis of diverticulitis)
The severity of symptoms will determined the treatment. There are two broad classifications used: uncomplicated diverticulitis (usually mild symptoms treated at home) and complicated diverticulitis (usually severe symptoms treated at hospital):
antibiotics to fight any detected bacterial infection
a liquid diet for a few days until intestines heal naturally
when symptoms improve, gradually add solid food to the diet
over-the-counter pain relief
a tube inserted to drain away any abdominal abscess (if formed)
surgery – this would normally be needed if:
certain complications occurred, such as:
puncture (perforation) in the colon wall
you have a history of multiple episodes of uncomplicated diverticulitis (flare-ups – see below)
you have a weakened immune system
Acute flare-ups are not uncommon. It’s reported 19 that 20% of people with diverticula develop a bout of diverticulitis at some stage in their lives. Best advice – eat lots of fibre and keep hydrated so that you can avoid them developing in the first place.
Two types of surgery for diverticulitis
The two main types of surgery involved with diverticulitis are:
bowel resection with colostomy (when inflammation has been too severe to connect the colon to the rectum, a colostomy will be the option. This involves making an opening in your abdominal wall and connecting it to the still-healthy part of the colon. Waste then passes through the opening into a bag. It’s possible in some cases that the inflammation will reduce and the colostomy can be reversed and the bowel reconnected)
A colonoscopy may be recommended at no less than six weeks after recovering from diverticulitis, particularly if no test was done in the previous year. This might be done in order to exclude any cancer. Some authorities consider 20 that there is no direct link between diverticular disease and colon or rectal cancer. Naturally, a colonoscopy cannot be risked during a diverticulitis attack.
When is eating fibre & a WFPB diet not recommended?
When there’s a flare-up of diverticular disease, especially when hospitalisation was required, it’s generally recommended that a low fibre/liquid-like diet is used as a short-term intervention. Primarily advised as a means of managing gut motility and acute pain, this period of so-called “bowel rest” usually involves abstaining from all solid foods for 2-3 days and consuming only a clear liquid diet, with water or other clear beverages usually being all that’s advised. Once the symptoms have disappeared (that is, when acute pain has subsided) and, of course, under the advice of their doctor, the patient would then be advised to transition to a high-fibre plant diet – ideally of the non-SOS WFPB type.
“An absolute must in treating acute diverticulitis is a high-fibre diet if patients wish to prevent complications and recurrences of disease.” 18
Can diverticulitis be reversed by diet?
Once you’ve been diagnosed with diverticulitis, you are strongly recommended to always liaise with your doctor about any dietary changes. However, to avoid recurrence of symptoms, there is little doubt that reducing the pressure within your intestinal tract is key. This is best achieved through eating a diet high in fibre and ensuring you are always fully hydrated.
How much water and fibre is enough? This is a well-debated topic, and was covered in the previous blog 21 , but my research shows that a person eating a balanced WFPB diet is likely to consume up to 100 grams of fibre daily. This is definitely a healthy level. One UK study suggested 22 that for every 5 gram increase in fibre consumed each day, the result was a 15% reduction in disease risk. The same study found that some whole plant fibre sources were especially protective against the disease, namely whole grains and fruits.
However, if a person chooses not to eat an exclusively WFPB diet, it’s generally advised that over 30 grams of fibre is the lower recommended limit. Personally, I would always suggest that WFPB is the way to go. Best be safe than sorry with something that can kill you quickly without you even knowing you had it in the first place.
In terms of daily liquid (ideally water, or black/green tea) consumption, a minimum of around 7 cups (1.75 litres) of water for women and ll cups (2.75 litres) for men is recommended. Plant foods contain mostly water, and so this will add to liquid intake to make it up to the WHO recommendation of 11 cups (2.75 litres) for women and 15 cups (3.75 litres) for men. 23
It’s been shown 2 that even eating just a standard vegetarian diet (with a high intake of dietary fibre compared with the standard meat-based Western diet), is associated with lowering the risk of getting the disease in the first place, of being admitted to hospital, and of dying from the disease. How much more for a WFPB diet with its higher fibre content? Other studies have shown similar results, stating: “Consuming a vegetarian diet and a high intake of dietary fibre were both associated with a lower risk of admission to hospital or death from diverticular disease.” 24
Dr John McDougall considers that it’s certainly worth changing to a high-fibre diet in order to relieve symptoms and prevent further diverticuli: “Contrary to what was once popular opinion, the addition of fibers in the form of brans or high fiber foods has relieved symptoms in 90% of cases of severe colon disease, even with recurrent pain and bleeding. A high fiber diet will also decrease the likelihood of developing new diverticuli. The diverticuli already formed are permanent herniations of the colon, and will not disappear except by surgical removal, which is rarely indicated.” 25
In the following short video, Dr McDougall also reassures us that the bleeding and infection within diverticuli can, in most cases, disappear by making simple dietary changes. The diverticuli themselves remain, although he considers that they would no longer be a problem, so long as a high-fibre diet is maintained.
Diverticulitis rises as fruit & veg consumption drops
Major studies have shown 626 beyond any doubt that the risk of developing diverticular disease goes down as fruit and vegetable consumption goes up – and, of course, vise versa. These studies produced the following results:
increased diverticular disease is associated with consumption of:
the strongest correlation of disease reduction is associated with consumption of:
consumption of all vegetable fibre also reduces disease risk
A further study 7 looked at the effects of using a high-fibre diet in the cases of 100 patients who had been previously diagnosed with acute diverticulitis. After 5-7 years on this diet, 91% of the patients remained completely symptom-free. The authors pointed out that the following respected organisations endorse and encourage the use of a high-fibre diet to prevent diverticular disease:
Can you eat nuts and seeds if you have diverticulitis?
The usual medical advice around people who have had diverticulitis is that they should avoid eating nuts, seeds, corn, and popcorn. Indeed, some doctors advise that everyone should avoid these foods as a means of avoiding the disease. However, there are at least two recent studies that have blown this unfounded advice out of the water.
A 2009 study 10 stated: “Without any good evidence, certain foodstuffs such as nuts, seeds, popcorn, and corn have long been implicated in the development of diverticulitis and are often advised against by physicians. They were thought to provoke diverticulitis or diverticular bleeding by causing luminal trauma. In a large prospective study of men without known diverticular disease, Strate et al found 31 that nut, corn, and popcorn consumption did not increase the risk of diverticulosis, diverticulitis, or diverticular bleeding.”
A 2012 study 32 stated: “Residue refers to any indigestible food substance that remains in the intestinal tract and contributes to stool bulk. Historically, low-residue diets have been recommended for diverticulosis because of a concern that indigestible nuts, seeds, corn, and popcorn could enter, block, or irritate a diverticulum and result in diverticulitis and possibly increase the risk of perforation. To date, there is no evidence supporting such a practice. In contrast, dietary fiber supplementation has been advocated to prevent diverticula formation and recurrence of symptomatic diverticulosis, although this is based mostly on low-quality observational studies.”
Whilst further research is useful, any advice to avoid nuts & seeds does not appear to be based on anything but unfounded conjecture. And, as shown in the 12-year long Seventh Day Adventist Study published in 2001, vegans who didn’t eat any nuts and seeds didn’t live as long as those vegans who did. This is because of the essential fats that nuts and seeds contain – allowing effective absorption of the phytochemicals and anti-oxidants that both groups are eating 3334
How common is diverticulitis?
“Diverticular disease [including diverticulitis] is the most common intestinal disorder.” 35
One study states: “In industrialized nations, diverticular disease affects up to 70% of individuals by 60 years of age, with symptoms that can range from mild gastrointestinal disturbance to incapacitating pain.” 36
Is diverticulitis age-related?
Whilst it’s been conventionally thought that it is an inevitable age-related condition – with the theory being that the intestinal walls tend to weaken as the years and decades pass – this theory can be shown to be untrue. Back in 1907, guess how many cases were recorded? 25! 36 That’s not 25% of the population, but 25 individual cases had been reported in the medical literature. And, as you can see from the graphic photograph above, any autopsy would have had little difficulty in missing diverticulitis if it had been present.
“Development of diverticular disease is not an inevitable part of growing older. The colons of people living in underdeveloped countries show a virtual absence of diverticular disease. Healthy, low, pressures in the colon happen when the diet is high in starches, vegetables, and fruits, with their generous content of fiber.” 25
Even in 1916, a study 37 reported that diverticulitis was still not sufficiently documented as a morbid disease in medical literature for it to merit medical recognition.
Diverticulitis – a late 20th Century disease
But in a 1971 study, by the WFPB pioneer Denis Burkitt and his team 38 , it was already recognised as the most common intestinal disease in the US population.
How could this have happened so quickly?
Denis Burkitt showed incredible insight by pointing out that it was most probably down to the fact that even by the 1970’s the Western diet had become low in fibre and high in animal products, processed and highly refined foods. Indeed, it took just half a century from the introduction of rolling milling of flour (which greatly reduced the natural fibre content) in the late 1800’s for diverticulitis to become common in the UK by the 1920’s.
Since then, things have gone from bad to worse.
A number of the first researchers to study diverticulitis nicknamed it a “20th century problem” and a “disease of Western civilisation.” 6
Denis Burkitt’s team back in the 1970’s included in their report 38 a simple diagram which they thought explained the process by which diverticula are formed:
It’s probably no surprise that the US and European populations have the highest rates of diverticular disease in the world, whilst it is rarely found in developing countries before, that is, they adopt the Western diet. 397
A 1985 study 40 , again by Denis Burkitt, compared Americans and Africans to see if there were differences in their rates of diverticulitis and other intestinal diseases related to low-fibre diets – namely, hiatus hernia and pelvic phleboliths41 . As Dr Greger pointed out in a video on this subject 42 , Burkitt found a huge difference in diverticulitis rates between the Africans eating the high-fibre diet (less than 1% of the population) and the Americans eating the low-fibre diet (more than 50% of the population):
Your poo can give a clue
This might not be the most tasteful subject, but you can tell a lot about the likely state of your intestines by checking on what your poo (stool or faeces) looks like. If you’re regularly constipated, and diverticula have already formed in the colon, stagnant faecal matter ends up clogged in the diverticula “bubbles”. 39 This can, in turn, trigger inflammation of the intestinal wall, resulting in the above-mentioned symptoms. The following chart is one of the standard charts used to get clues from your poos:
The Bristol Stool Chart provides a graphic version of various stool samples.
Developed by Dr. Ken Heaton from the University of Bristol in the late 1990’s, it’s used primarily as a clinical communication aid in categorising stool types 43 .
It’s only meant to be an unofficial guide, but does allow us to get a general idea of the classification of our poo, providing, thereby, a reasonably good indicator of both the diet we’re eating and the likely state of our intestines.
types 1 and 2 are typical of a constipated individual
type 3 is borderline normal
type 4 is the “gold standard for the perfect stool”
type 5 is heading in the direction of diarrhoea
types 6 and 7 reflect an individual in diarrhoea distress
If you want to delve deeper into the subject of bowel movements and constipation, Dustin Rudolph, PharmD has written a useful article. 44
It’s worth repeating that the balance of gut bacteria can be altered by chronic constipation and eating a low-fibre diet. Rather than a colon full of “good” (healthy) bacteria, there’s an increase in “bad” (infectious) bacteria that populate the colon. And it’s the presence of the latter bacteria that can further increase the chances of an infection developing.
Low-fibre diets do NOT cause diverticulitis!
Just to confuse the issue, a 2012 North Carolina study 45 came up with completely different conclusions than everything else that’s been said above about diverticulitis (and, of course, constipation) being powerfully linked to low-fibre diets. The study concluded:
“In our cross-sectional, colonoscopy-based study, neither constipation nor a low-fiber diet was associated with an increased risk of diverticulosis.”
By understanding the reason that they found no association, we can learn something about the quantity of fibre necessary to make a significant difference to your risk of developing chronic constipation and/or diverticulitis, plus we can learn a lot about how clinical trials can come up with misleading information.
In this study, they took two groups and carefully ensured that one group received only 8 grams of fibre a day while the other group received 25 grams of fibre a day. When they compared the results, there was no significant difference in the rates of diverticulosis and, thus they announced to the world that we do not need to bother eating a high-fibre diet in order to maintain good gut health.
The story was taken up all over the world, with headlines like:
“Diets high in fiber won’t protect against diverticulosis, study finds.“4647
“High-fibre diet may not protect against diverticulosis.”48
“Paleo Diet: More Evidence That Fiber is Not A Good Thing.”49
And not only did the Paleo crowd get involved and believe the study findings, even medical journals jumped on the band wagon, quoting the conclusions of the above study:
“Diverticulosis and dietary fiber: rethinking the relationship…A high-fiber diet does not protect against asymptomatic diverticulosis.” 50
So, what’s going on here?
Firstly, good news about bad habits is always attractive for those who want to justify their own bad dietary habits – tucking into a juicy beefburger and fries with impunity, rather than having to worry about eating all that rabbit food!
However, the fatal flaw in the study was identified pretty quickly by other studies, including the following:
“Most importantly, how this study is interpreted is limited by the overall low-fiber intake within the study population. Although the authors performed analyses stratified by fiber intake and found no significant difference between those in the lowest (2.5–10.1 g) and highest quartiles (18.4–50.3 g) of fiber intake, few patients in the uppermost quartile had a true high fiber intake. An analysis reflecting clinical recommendations of high-fiber (>25 g) vs low-fiber (<14 g) diets may have yielded different results.” 51
To clarify just what this flaw of the study was, Dr Greger 52 drew an excellent analogy with early vitamin C studies. It takes around 10 mg of vitamin C a day to avoid developing scurvy 53 .
Back in the 1700’s, James Lind 54 wondered if scurvy in sailors could be avoided if they were given wedges of lemon each day. So he tested his theory. One group were given one wedge of lemon, and the other group were given three wedges of lemon a day. He found no difference at all between the groups, and the same ratio came down with scurvy.
So, did this prove that low vitamin C levels are not associated with the development of scurvy? Of course not. In order to prevent scurvy, it’s necessary to ingest at least 10 mg of vitamin C, and a single wedge of lemon only has around 2 mg. So, even with three wedges of lemon, you’re still only getting around 6 mg.
See the analogy?
The group eating the highest amount of fibre in the above North Caroline study 45 were only eating around 25 grams of fibre a day, which is less than the US minimum recommended daily allowance of around 32 grams. As Dr Greger says: “They didn’t even make the minimum. So they compared one fiber-deficient diet to another fiber-deficient diet—no wonder there was no difference in diverticulosis rates.”
Whenever looking at any study results that appear “too good to be true”, it’s always worth checking on what was compared with what – after all, even a McDonald’s Big Breakfast is healthy when compared with…smoking tobacco or inhaling asbestos!
As with many things in life, simple is best. The best form of cure for diverticular disease is prevention. And the best form of prevention is undoubtedly provided by eating a high-fibre diet, keeping well-hydrated, and getting plenty of regular daily exercise.
I can’t really think of a better way of ending than by quoting a closing comment by Dustin Rudolph, PharmD, writing for T Colin Campbell’s Center for Nutrition Studies (CNS), made at the end of his article on diverticular disease:
“Eat plants. Get lots of fiber. Live happy. And avoid doctors and pharmacists if at all possible by adopting a whole food, plant-based lifestyle. Your body will thank you for many years to come.” 18
A fistula, in this case, is an abnormal passage between a hollow or tubular organ and the body surface, or between two hollow or tubular organs. In this case, it is more commonly between the intestine and the bladder. [↩]
Pelvic phleboliths are are round clusters of calcium that develop in the walls of a vein. They can vary in size but are usually around 5 mm across. They most commonly appear in the veins surrounding the pelvis. They can be caused by constipation and straining, which can damage pelvic veins. [↩]
Scurvy is a disease resulting from a lack of vitamin C (ascorbic acid). Early symptoms include weakness, feeling tired, and sore arms and legs. Without treatment, decreased red blood cells, gum disease, changes to hair, and bleeding from the skin may occur. As scurvy worsens there can be poor wound healing, personality changes, and finally death from infection or bleeding. [↩]
Studies suggest 12 that around 20% of people in Westernised countries suffer from constipation. That’s a lot of unpleasant and largely unnecessary toilet trouble by any standards. But is there a simple, drug-free remedy? You can bet your beans and greens there is!
Fibre, fibre, fibre
The most common lifestyle choice associated with the development of constipation is eating a low-fibre diet.
It still comes as something as a surprise just how many people are completely unaware that fibre can only be found in foods derived from plants – fruit and veg, beans, whole grains, etc – and that there is ZERO fibre in meat, dairy products, and eggs.
The average daily fibre intake in the UK is 17.2 grams/day for women and 20.1 grams/day for men, with a government recommendation of a minimum of 30 grams/day 3 . In the US, the recommendations vary from 19-38 grams/day, whilst US fibre intake is even less than the UK, at around 16 grams/day 45 . And, because these are averages, it means there are plenty of people eating considerably less than this.
A previous blog 6 discussed fibre in more detail, and pointed out that eating as much as 100 grams of fibre daily was quite normal in earlier human evolution.
In those countries where traditional diets contain much more fibre, it’s no surprise to find that constipation is much less common. But how can we know that it’s the fibre that’s making so much difference? Well, studies have looked at the changes that occur when such countries adopt the modern Western diet, which is much lower in fibre content. And what they’ve found is that constipation prevalence increases. 78
Constipation by country
There’s a very detailed list of reported constipation cases available at cureresearch.com 9 , but the following selective chart from a 2008 study 10 shows a common finding: namely, that women tend to suffer more than men.
Problems arising from constipation
There are a number of complications which may arise from constipation 1112 , including:
haemorrhoids (from “straining at the stool”)
faecal impaction (also called malignant constipation), which may lead to:
encopresis (where soft stool from the small intestine bypasses the impacted faecal mass in the colon)
How to prevent and alleviate constipation
It’s pretty obvious that the most sensible and natural method will involve increasing fibre content in the diet.
In children, studies show 1314 that a lower intake of dietary fibre differentiates children with chronic constipation from those who have regular bowel movements. It’s so sad that children have to undergo such suffering simply because their parents and carers fail (whether through ignorance or conscious choice) to feed them a diet that maintains their gut health. Of course, it’s not just the problem of constipation that’s at issue here; maintaining a healthy gut microbiome from early life is vital for overall health through childhood and into old age 15161718 . And it’s such an obvious yet largely unappreciated fact 19 that our GI tract (along with all the trillions of essential bacteria, fungi and other microbes therein) is best maintained by a whole food plant-based diet rather than a diet of processed and/or animal foods.
As would be expected, therefore, additional studies show that increasing dietary fibre improves constipation and significantly reduces the need for laxatives in all societal groups:
Naturally, the first and best option is to increase the consumption of high-fibre foods. This is because, by eating whole plant foods, we don’t just facilitate easier gut transit, but the fibre itself and the natural healthy bacteria included with plants act as probiotics and prebiotics for our gut bacteria, and a variety of plants provides a vast array of minerals, vitamins, and an almost inestimable number of beneficial phytochemicals.
However, there are situations where chewing away on fibrous plant food is not an option, and so, in the following cases, fibre supplements may be the best option:
individuals lacking teeth (edentulism)
patients who can’t swallow easily or at all (dysphagia)
Prescribing laxatives is a very general knee-jerk reaction of medical professionals. They seem to choose this because they don’t appear to believe their patients have the wherewithal to significantly alter their diets. However, suggesting fibre supplements, in the case of the above two conditions, or changing to a high-fibre diet, in the case of most patients, is far more successful than merely pouring laxatives down your throat while still eating the same constipating diet. When the second best alternative (fibre supplements) are offered, evidence suggests 24 that around 60% of constipated patients can dispense with the laxatives they had been previously taking.
Different types of fibre supplements
The following have been shown to be effective for constipation relief:
psyllium (Metamucil) 25 (although prunes have been shown 26 to be more effective than psyllium)
But, I repeat, the first and best option is to transition to a plant-based diet (ideally non-SOS WFPB) unless, of course, you have no teeth or cannot swallow easily. And, even the latter two cases, I would suspect that there may be some way found to ensure whole plant foods are eaten, even if they have to be pulped or liquidised to some extent. I have some personal experience of this situation, since my father developed COPD29 and dysphagia. Being crippled and having to be cared for my my mother, she was told that he would only ever be able to eat pureed food. However, she found that with some careful selection of foods, he was able to eat “solid” food almost until the time of his eventual death.
Dehydration & constipation
Even mild dehydration is a very common factor in cases of constipation 3031 . This has also been found 20 to be the case in young constipated children. And it’s easy to understand why this is the case, and how it links inextricably with diet, when you realise that whole plant foods contain loads of water, while processed and animal foods can contain considerably less – and also usually contain loads of dehydrating salt.
Becoming dehydrated, without being aware of it, is much easier and more widespread than most of us realise. This can be seen from a US study 32 which found a shocking 75% of US citizens were chronically dehydrated.
In patients with functional chronic constipation, it’s been shown 33 that combining fibre and fluid (25 grams and 1.5-2.0 litres, respectively) on a daily basis was more effective for constipation relief than simply taking fibre alone.
It’s no surprise, then, that Dr Greger includes water consumption as one of the essential items in his Daily Dozen list 34 , stating that “…authorities from Europe, the U.S. Institute of Medicine, and the World Health Organization recommend between 2 to 2.7 liters of water a day for women. That’s 8 to 11 cups a day for women, and 10 to 15 cups a day for men. Now but that’s water from all sources–not just beverages–and we get about a liter from food and the water our body actually makes. So these translate into a recommendation for women to drink 4 to 7 cups of water a day, and men 6 to 11 cups, assuming only moderate physical activity at moderate ambient temperatures.” 35 .
Constipation & cow’s milk
Many children with chronic constipation are found 36 to be allergic to cow’s milk, manifesting IgE antibodies37 to cow’s milk antigens38 . It’s always worthwhile for parents to ensure that any difficulties occurring during potty training are not associated with constipation resulting from the child drinking cow’s milk.
This is no insignificant matter, since consumption of cow’s milk has been found 39 to be significantly higher in infants and children with constipation and anal fissure than in those without these disorders.
And it gets even worse. Colonoscopies revealed 40 that around 50% of constipated, cow’s milk-allergic children and adolescents had lymphoid nodular hyperplasia41 , compared with 20% of controls. The same study also found that around 33% of all cow’s milk-allergic individuals had a significantly higher number of intraepithelial T cells42 , indicating an enhancement of local immune responses against food antigens. Another study of children with lymphoid modular hyperplasia found 43 that in 43 of the 52 individuals a diagnosis of cow’s milk or multiple food hypersensitivity was made.
Such activation of the immune system is known 44 to affect gastric motility45 , thus indicating a likely role for an immune response to food antigens in cases of constipation.
Cow’s milk or soy milk?
Cutting out cow’s milk totally, in the diets of those children with cow’s milk sensitivity and constipation, has been shown 46 to result in significant improvement in up to 66% of cases.
In a small-scale study 47 of children with constipation, 100% of the participants had full resolution of chronic functional constipation when soy milk was used as a replacement for cow’s milk.
A further study found 48 that when cow’s milk was reintroduced, constipation returned within 5-10 days.
Previous blogs 4950 have discussed in much more detail the range of health issues associated with cow’s milk. In basic terms, for all humans, irrespective of age, there’s absolutely no nutritional need for “baby calf growth fluid” 51 to be included in the diet. And, for a significant number of both children and adults who experience constipation, it would seem a sensible plan to try cutting out cow’s milk completely to see whether relief of symptoms follows.
So, getting lots of fibre, drinking plenty of fluids and avoiding cow’s milk seem to be the major routes towards non-drug prevention and treatment of constipation in all age groups. One area we haven’t covered is regular physical exercise, which, counter to popular belief, does not have any overwhelming study evidence to support its value for constipation treatment or avoidance. Some studies consider that it can be an important adjunct for males 52 and females 53 of all age groups in the prevention and treatment of constipation. However, other studies, including the following 2017 French study, question whether increasing exercise per se has any positive effect:
“The benefi[t] of increasing water intake or daily physical exercise in the treatment of chronic constipation have a lack of evidence, except specific situations such as elderly, hospitalized, institutionalized, dehydrated people or people consuming fluids less than 500mL/day. Change in environmental defecation conditions or bowel habits are probably anecdotal recommendations.” 54
Yet other authorities consider 55 that, in some cases of particularly intense exercise, constipation can be worsened. More research is needed on which level of activity (stationary yoga movements, gentle walking or marathon running, for instance) has what effect on constipation.
Whilst lack of exercise is particularly important as we age and run the risk of becoming too sedentary 56 , the increasing rates of childhood obesity – and the associated reduction in physical exercise – are reported by some studies as revealing a worrying increase in cases of constipation and other GI health concerns 5758 .
My personal experience is that the effects of exercise appear to be determined, at least to some extent, on the quality of diet you are consuming. If you’re already eating a low-fibre diet and then exercise, I have no doubt that it might lead to increased constipation; however, when a high-fibre diet is your norm, exercise may not have the same effect. A comparison study would be of interest in this respect.
What all studies agree on, however, is that the main and overreaching factor of importance in avoiding and treating constipation is fibre, fibre and more fibre.
So, in conclusion, whilst it’s easy to say that best means of achieving healthy GI tract activity is to follow a varied WFPB diet, keep hydrated and ensure that you get plenty of daily exercise, when we have had a lifetime of practising ingrained and unquestioned habits, it can be really difficult to make such lifestyle and dietary changes. However, ensuring that our children do not fall into bad habits will both protect them and encourage us to embrace healthier practices ourselves.
Chronic Obstructive Pulmonary Disease (COPD) is an umbrella term used to describe progressive lung diseases including emphysema, chronic bronchitis, and refractory (non-reversible) asthma. This disease is characterised by increasing breathlessness. [↩]
IgE antibodies: If you have an allergy, your immune system overreacts to an allergen by producing antibodies called Immunoglobulin E (IgE). These antibodies travel to cells that release chemicals, causing an allergic reaction. This reaction usually causes symptoms in the nose, lungs, throat, or on the skin. [↩]
Antigens are toxins or other foreign substances which induce an immune response in the body, especially the production of antibodies. [↩]
Lymphoid nodular hyperplasia (LNH) generally presents as an asymptomatic disease, but it may cause gastrointestinal symptoms like abdominal pain, chronic diarrhoea, bleeding or intestinal obstruction. [↩]
Intraepithelial T cells (IETs), residing at the epithelial barrier in the gastrointestinal tract, are an epitome of tissue-resident T cells. Tissue-resident T cells are long-lived, nonrecirculating T cells that provide rapid immune responses independent of peripheral T cell recruitment. [↩]
Gastric Motility: contractions of gastric smooth muscle that serves two basic functions: ingested food is crushed, ground and mixed, liquefying it to form what is called chyme. Chyme is then forced through the pyloric canal into the small intestine, a process called gastric emptying. [↩]
There are a number of methods to ensure that toddlers eat healthily, and there’s probably been no other time in human history when it’s been more important to do so. Child obesity and all its associated metabolic diseases are hitting children at ever younger ages 123 . Whilst it’s so easy to blame Big Business and national governments, the primary responsibility for ensuring our children grown up healthy is now, as it always has been, mostly in the hands of their own parents and carers.
Definition of terms
Although not written in stone, the stages of early childhood are conventionally understood as the following:
newborn – between 0 and 2 months
infant – between 2 and 12 months
toddler – between 12 months and 4 years
Getting it right from the start
The most important time to ensure the development of healthy eating habits is arguably during the early weaning process – that is, the period when the baby is transitioning from mother’s breast milk to solid food. I am taking for granted that we would all agree the newborn’s ideal first nutrition (for around the first 6 months) should always be exclusively mother’s breast milk whenever possible. All the evidence points in this direction 456 .
Bad habits are hard to break
Between around 6 and 12 months of age, the infant will be introduced to “solid” food. It’s during this stage that major mistakes can be made, and bad eating habits (food high in calories and low in nutrients) can be set in motion.
If, however, appropriate food (high in nutrients and sufficient in calories for growth) is introduced, ingrained bad habits within the infant and toddler stages can be avoided, with the remaining years of childhood (and probably adulthood) thus standing a much better chance of being free from the need to put endless effort into undoing such habits – yo-yo dieting, continual fighting to escape the pleasure trap, with all its tempting and addictive bliss points 7.
The importance of good example
Whether or not less-favourable eating habits have been established, parents and carers need to ensure that they act as good examples. This means:
eating a healthy and varied balance of foods themselves
eating at regular times
sharing meals – making each meal a special family event, rather than simply eating separately in front of the TV
encouraging toddlers to eat 3 meals a day plus 2 healthy snacks. This can avoid those hunger pangs that can result in unhealthy ‘grazing’ between meals and then overeating during meals
Children who grow up seeing their parents and carers forever on diets or bingeing on unhealthy foods is not something that will act as a good example.
One recent story I heard was of a nutritionist who was asked to intervene in a family where the young child refused to eat anything that even appeared to be a vegetable or a fruit, preferring instead to eat a diet existing more or less solely of sweets, crisps and cakes. The nutritionist advised that containers of bite-sized carrots and celery be left around the kitchen for the child to be attracted to eat. The nutritionist then walked past the veg and said something along the lines of “Oh look! How lovely! Carrots. I love them” and then tucked into them with glee. When the father was asked to do the same, as a means of giving positive feedback to the child, he picked up a carrot, bit into it and pulled a face that would have been better suited to a person who had just swallowed a bumble bee. Naturally, the child saw his father’s reaction and the nutritionist could immediately identify the major reason that the child had developed such unhealthy habits.
Toddlers in the kitchen
Even from the youngest age, infants will be influenced by the sorts of foods they encounter. This isn’t just a matter of flavours, but also of smell, texture, colour, and general variety – the colours of the rainbow.
The relationship parents and carers have to matters relating to food preparation itself will have an effect on the growing child. Involving the toddler from an early age in making meals and understanding the nature of different foods can be of great help in ensuring the child grows up with knowledge about and control over dietary matters.
Any parent will find that toddlers simply love experimenting with the selection and preparation of food. This playful experience is a great way for them to try different foods in the kitchen. It, along with meal times, should be a fun way to spend time with the family. The idea of simply placing already-prepared meals in front of a toddler may be attractive in terms of saving preparation time; however, doing so would tend to miss the exciting and productive times when he or she (or a group of toddlers, be they friends or siblings) could be involved in handling, selecting, chopping, peeling, and even cooking (with careful supervision, of course).
I remember that when I was young I asked my mother what tongue was – you know, those greyish-red slices of meat that bear no resemblance to that huge, dripping muscular organ lolling out of the mouths of cows. I’d been eating it for years and it hadn’t dawned on me that what we called slices of tongue was actually part of a dead animal. I mean, they called candyfloss candyfloss, but you don’t floss candy with it! Anyway, once I discovered what it was, I never touched it again. Had I been responsible for cutting it out of the mouth of the dead cow and then slicing and boiling it, perhaps I would have developed an aversion to it at an even earlier age. Who knows?
Toddler or parent temptation?
Avoiding the temptation to give in to a toddler’s potential demands for sweets and treats is increasingly difficult for parents, what with the ubiquitous advertising campaigns and availability in toddler-height shelves in most shops these days. Even when it comes to those special times, it’s still so important to avoid making unhealthy junk foods a treat or a central part of festivals, birthdays and other celebrations.
If a toddler grows up thinking that a real treat is enjoying a healthy salad rather than being thrown a bag of prawn cocktail crisps or a bag of Haribo Starmix, it’s a pretty good indication that something has been done right!
Of course, parents themselves have to engage in the same fight with sweet and junky temptations that they may well have had since their own childhoods. In this case, fighting one’s own natural desires for sweet indulgence is a preface to allowing one’s children to grow up with more freedom from cravings and learned preferences associated with such toxic foods.
And it hardly needs saying saying that using foods in any way to establish or maintain emotional control is to be avoided. As soon as emotional states (positive or negative) are inextricably linked to food, problems can arise. The art of developing a sense of well-being which is separate from the need for oral satisfaction is something that one would wish all children to learn at an early age. It allows them freedom to seek emotional satisfaction and achievement in other more productive spheres of life.
Eat when hungry
Thus, it’s useful for toddlers to grow up learning that they eat when they are hungry – not when they are forced to do so or because they are bored or depressed.
In any case, toddlers have tiny stomachs which, if filled with unhealthy foods, will leave no room for more essential nutrients. This is where portion control comes into its own. In order to ensure that the toddler does not get used to over-eating, the type and quantity of foods they are presented with should be taken into consideration. Just as there should be no justification for “forcing” an infant or toddler to eat something that he or she does not want to eat, it is equally unhelpful for them to force food down when their body is telling them that they have eaten enough.
Allowing infants and toddlers to exercise some choice in the foods they put into their mouths is advisable – so long as the selection is from healthy and interesting foods. If they don’t want to eat at the moment, fine – be patient and wait until they feel hungry. In the meantime, they can see their parents enjoying the same sorts of food, without having made a big issue of the child’s not eating at that moment. A relaxed atmosphere around the dining table is always likely to produce healthy and easy-going dietary habits in the child.
When hunger hits and ‘seconds’ are required, they should be from a selection of vegetables or fruit. If the toddler wants more immediately after having eaten their meal, it might be a good idea to encourage them to wait for a little while in order to let the food “settle” – allowing leptin to do its job 8 – before they have extra portions.
Learning portion control early in life is a useful means of preventing over-eating in future years. This is not usually a problem, however, with those who eat a non-SOS WFPB diet, since the range of foods within this dietary regime tend to be self-limiting. It’s only when the stomach is filled with high calorie/low nutrient alternatives 9 that over-eating is something that parents should be really concerned about – both for themselves and their children – being that processed foods are carefully manufactured to be addictive “pleasure traps” as they hit those “bliss points” 10 .
Anticipation can be better than participation
Learning ‘satisfaction-delay’ is a really good skill for children to learn young. If a toddler gets what he or she wants immediately upon request, they don’t learn how to delay pleasurable experiences, and learning how to live with the delayed pleasure of eating is a useful skill that spills over into most aspects of child and adult life.
“Delaying gratification isn’t a new concept. Back in 300 BC, Aristotle saw that the reason so many people were unhappy was that they confused pleasure for true happiness. True happiness, according to Aristotle, is about developing habits and surrounding yourself with people who grow your soul.” 11
Variety (within reason) matters
Introducing a variety of foods is important and, as stated before, not forcing a child to eat a particular food, if they feel a strong dislike for it, is a sensible move. The chances are that they will change their minds later and try the foods if they see adults enjoying them and not making an issue of them. Patience is the key. This planet of ours grows so many wonderful edible plants that finding alternatives should never be a problem for the attentive parent.
Whilst toddlers are, of course, too young to receive pocket money and run the risk of spending it on sweets etc, any food choices they are able to make at this young age should be from as healthy a range of options as possible. This means keeping only healthy foods in the house and trying to avoid the aisles in supermarkets which draw their attention to unhealthy foods – unfortunately, this is virtually impossible in the modern Western food shopping experience.
Take care with carers
Parents should make their dietary rules very clear to any carers who take responsibility for the toddler. Bad habits learned from carers can cause conflict in the child when they return to their parents and find that they are being told a different story about what dietary habits are or are not acceptable. This applies to both the type and quantity of foods themselves and the regularity and form of dining habits.
Thinking before drinking
In terms of drinks, toddlers should not get used to filling up on sugary drinks. It should go without saying that infants receive their best source of liquids from their mother’s breast milk. Providing drinking fluids during weening is, of course, a natural and essential route, so long as the liquid provided is plain water.
It’s hard to find any authority that would advise parents to give their toddlers fizzy/sugary drinks. The best thing is to avoid all sugary drinks completely so that the child becomes accustomed and perfectly content with simple tap water.
Parents would be wise to do a bit of careful research before deciding to follow the crowd in giving their toddlers cow’s milk. Parents usually feed cow’s milk to their children because they had it themselves and it’s something that is, well, just done! However, much of this is based on an arguably inaccurate belief that cow’s milk is necessary to ensure children get enough calcium 12 . There are some pretty convincing arguments, based on solid research 1312 , that would caution against feeding cow’s milk to your child, especially when there are plenty of fortified plant milk alternatives 14 to choose from.
It may come as a surprise to some people, but even fruit juices are not an ideal drink 15 , especially if they have added sugar or artificial sweeteners. If, however, they are to be given to toddlers, they should be diluted with water.
The foregoing is by no means a comprehensive overview of the many ways in which parents can encourage healthy eating habits in their children during the earliest stages of their lives. For my part, I wish my parents had followed even a few of the ideas outlined above. My overly sweet childhood diet resulted in countless rotten teeth and fillings during my adolescent years. This has been accompanied with a life-long struggle against using sweet and fatty junk foods as a reward for a tiring day, a pick-me-up when feeling a little low, and a treat whenever there’s a “y” in the day!
This is why engendering good dietary habits from a young age is so very important. It’s easier to do the right thing when you don’t have to continually undo the wrong.
I wouldn’t wish on anyone a lifetime of being good at bad habits.
It might sound a bit odd, but apparently it’s possible to improve metabolic measures related to blood flow simply by hanging upside down. However, get it wrong and you might end up killing yourself.
It’s well-known that regular aerobic exercise is good for the heart. But various yoga positions also appear to do a similar trick without the need for so much sweating.
One particular yoga pose of specific interest is the upside down position. Of course, as you can see below, there are plenty of different ways of achieving this.
What are the upside down benefits?
A 2011 review 1 into the benefits of yoga in general considered that upside down (or inverted) yoga poses were of benefit to the cardiovascular system:
“Inverted poses encourage venous blood flow from the legs and pelvis back to the heart and then pumped through the lungs where it becomes freshly oxygenated. Many studies 234 show yoga lowers the resting heart rate, increases endurance, and can improve the maximum uptake and utilisation of oxygen during exercise.”
There are plenty of yoga websites 5678 that give advice on the best way to achieve this inverted pose – variously called supported headstand, sirsasana, inversions, and so forth.
Any yoga’s good yoga
Naturally, this is not the only yoga pose that studies have shown has health benefits. Studies suggest a wide range of benefits, such as:
However, you should be warned that this is not one of those things where a little is good and a lot is even better. Too much inversion can kill 20 .
In 2009, a guy called John Jones, who lived in Utah, died after spending 28 hours stuck upside down in a cave 21 , most likely from asphyxiation.
Upside down lungs
It transpires that our lungs evolved to sit on top of all the other organs for a very good reason. They are such delicate organs that it doesn’t take them long to get squashed by the larger and heavier organs such as the liver and intestines that usually sit below them. 22
This isn’t a problem for sloths, since they have their lungs “taped” to their ribs 23 .
But for us mere humans, having our heads directly underneath our feet for extended periods of time means that the lungs simply can’t absorb enough oxygen given the restricted space they have to work within.
Upside down brain
And it’s not just our lungs that have difficulty. Our bodies are set up to move blood around when we’re upright. Our blood vessels are customised to make sure blood doesn’t pool in our feet. This system is a “one-way street”, since our bodies didn’t evolve to prevent blood from pooling in the brain. This is patently not the case with bats. They have one-way valves in their arteries that prevent blood from flowing backwards. This is why they are able to hang upside down without the blood rushing to their heads 24 .
However, unlike bats, Batman would get into all sorts of vascular trouble (with or without the help of Robin) – ruptured blood vessels and potential brain haemorrhage included.
Upside down heart
And the heart is no lover of too much life down under 25 . It’s thought that heart failure accounts for most upside down fatalities. Just as with the brain, when the heart is above the head, it pumps more slowly and starts to receive more blood than it has the capacity to deal with at any one time. The result is that it begins to have a hard time maintaining blood pressure. Eventually, it will lose its ability to move sufficient blood around to maintain all the body’s essential functions.
Hanging around for too long will eventually kill you – a risk which increases as we age or if we are sick.
Inversion can be torture
It should be remembered that inversion was used as a torture method is ye olde days. It combined pain with a smattering of humiliation. Often the torture of choice for those sinners with unorthodox beliefs, it was used by the Romans with Christians and the Spanish with Jews and Muslims 2627 . The Japanese even have a word for it – Tsurushi or “reverse hanging” 28 .
Nice to see how relaxed that monk-like executioner appears!
Another thing they used to do was to keep the victim inverted for some time and then make them stand upright again. Apparently, this is very painful as the blood pools to the feet again. Of course, they’re then hung upside down again. This process usually kills them within 8 to 10 hours.
Oh how inventive we humans are…
It’s probably the case that any exercise is good exercise – whether it’s resistance training with weights, aerobic, or yoga. The important thing is to ensure you get plenty of regular daily exercise – either 90 mins low-moderate intensity (e.g. walking) or 45 mins of high-intensity exercise (e.g cycling, running, or rowing). It’s generally suggested 29 that you can work out your maximum heart rate by simply subtracting your age from 220. Then you can think of low-moderate intensity as being 50 – 70% of the resulting figure, whilst high-intensity would be 70-85%.
Spending a little time upside down appears to be something worth considering – however, some methods of achieving this are better than others…
Tackling obesity without exercise or dietary changes? Everyone’s heard of fat tissue (also called adipose tissue), but what about brown adipose tissue (BAT) and “beige” adipose tissue – ever heard of them? Although sounding pretty unappetising, these adipocytes1 share the unique ability of being able to convert chemical energy into heat and, thereby, play a critical role in promoting something called non-shivering thermogenesis – a little-known process that is central to the human species’ ability to spread across the globe and, as an interesting sideline, can potentially help in weight-loss without even having to lift a single barbell or place a tentative trainer on that running machine gathering dust in your garage. Or is it just too good to be true?
BAT & beige adipocytes
Until relatively recently, the physiological role of BAT and beige adipocyte depots were thought to be limited to small mammals and only relevant to humans when they were neonates (newborn infants). Puppy fat or baby fat was thought to all-but disappear with the passing years into adulthood. However, the discovery that there’s more BAT in adult humans than previously thought, has led to studies which show enthusiasm for BAT’s potential role in treating obesity and other disorders caused by sustained positive energy balance (more calories in than out). Adult humans having more BAT than previously thought was revealed 23 during routine scans (FDG-PET scans) 4 to detect metastatic cancers. 5 Autopsies were also able to reveal these fat concentrations. 6
Brown & white fat
BAT (often abbreviated to “brown fat”) is found in virtually all mammals, but notably in newborn humans and mammals that hibernate 7 . Of course, the usual white adipose tissue (“white fat”) that we think of when we talk about fat is found in far higher quantities. 8 . The following provides an overview of the differences between the brown and white fat tissue:
The main differences between brown and white fat can be summarised as:
white contains a single lipid droplet while brown contains numerous smaller droplets
brown contains a much much higher number of (iron-containing) mitochondria – hence the brown (rusty) colour of the tissue 9
brown contains more blood capillaries than white – hence a better oxygen supply, more nutrient-provision and the ability to distribute the produced heat throughout the body
Two types of BAT
BAT itself can also broken down into two types which have similar functions but are located in different cell populations within the body: 10
brown adipocytes found in comparatively larger separate deposits within the body, and
“beige” or “brite” (“brown in white”) adipocytes found interspersed within white adipose tissue and which develop out of white adipocytes under the stimulation of the sympathetic nervous system (SNS) 11
BAT in infants & adults
BAT in infants eventually “turns into” white fat in adulthood. In infancy, however, it tends to be located in the following “depots” within the body:
It’s still not absolutely clear whether these adult BAT depots are the “classical” brown or the beige/brite fat. 21 . However, BAT is metabolically active in adult humans 22 and decreases in quantity as we age 23 . Another characteristic of BAT is that it becomes more visible (that is, becomes more metabolically active) with cold exposure – as can be seen by analysing it with PET scans.
BAT & thermoregulation
The primary function of BAT is thermoregulation. That is, ensuring the body remains sufficiently warm in cold environments. It achieves this autonomic heating of the body in two ways: firstly, through shivering thermogenesis (causing muscles to shiver) and, secondly, through non-shivering thermogenesis (as the name suggests – heating the body without shivering) – an adaptive thermogenesis response. The first option, shivering thermogenesis, will certainly warm up the body, but at the expense of using up relatively more precious energy.
However, the unique ability of BAT to convert energy stores (brown fat) into heat (without needing to use energy-sapping shivering) is achieved through a process within BAT mitochondria (the energy-producing cellular power plants). Instead of the usual process, where ATP (the energy molecule) is produced during oxidative phosphorylation, a protein called thermogenin or UCP1 (Uncoupling Protein 1) promotes a proton leak in the inner membrane of the mitochondria, dissociating the oxidative phosphorylation of substrate from the generation of ATP. In essence, this results in an increase in non-shivering thermogenesis, where the metabolic rate increases, and chemical energy is shunted into heat energy that can then spread around the body via the bloodstream.
This means the endothermic organisms (you and me) stand a better chance of survival against unfavourable environmental conditions with the least possible consumption of energy stores 24 . This can be seen in a little more clearly in the following diagram:
Just to be clear, all cells of endotherms are able to give off heat to some degree, particularly when body temperature is below a regulatory threshold; but BAT is highly specialised for this non-shivering thermogenesis. This is largely because of two of the features mentioned above: firstly, each BAT cell has a higher number of mitochondria compared to typical cells and, secondly, these mitochondria have a higher-than-normal concentration of thermogenin (UCP1) in the inner membrane.
Why do newborns have so much BAT?
In newborn infants, BAT comprises around 5% of body mass (located on the upper half of the spine and toward the shoulders). At this age, infants are at a much higher risk of hypothermia than adults. This is largely because of the following:
underdeveloped nervous systems that don’t respond quickly and/or appropriately to cold via vasoconstriction (the contraction of blood vessels in and just below the skin)
inability to move away from cold materials or air currents or towards warmer materials/environments
low amount of musculature and an inability to shiver (shivering thermogenesis)
lack of thermal insulation such as subcutaneous fat and fine body hair
higher ratio of body surface area (proportional to heat loss) to body volume (proportional to heat production)
higher proportional surface area of the head
the obvious inability to use adult ways of keeping warm – putting clothes on, exercising, drying their skin, etc
Thus, heat production in BAT provides infants with an alternative means of heat regulation.
Evolutionary advantage of BAT
Mammals (and birds, to some extent) have the unique ability to maintain their core temperature independently of the external environmental temperature. This homeothermic 25 ability has allowed great evolutionary success compared to poikilotherms26 . 27
The main components of this response to temperature are:
From an evolutionary point of view, excess energy expenditure aimed at maintaining core temperature represents a trade-off between survival and the maintenance of energy stores, since energy availability will usually represent a major limiting factor to growth and reproduction. Thus, moving from an insulative response (energy neutral), to a non-shivering and eventually shivering thermogenesis will require a progressively greater dissipation of energy stores, as can be seen in the following chart.
Over recent evolutionary development, humans gained the ability to “control” their environment by using clothes and controlling the temperature in their buildings. As a result, cold exposure is a relatively rare condition and, unless acclimatised, individuals would tend to respond by shivering thermogenesis – where heat is a side product of uncontrolled shivering – also known as muscle fasciculation29
Losing weight & improving health with BAT
Recent discoveries regarding BAT may, it’s claimed, lead to new methods of weight loss, since brown fat (when exposed to cold temperatures) takes calories from normal fat and burns it. As well as this, adaptive (non-shivering) thermogenesis also appears to promote glucose disposal. To test this weight-loss ability of BAT, it would involve exposing subjects to cold temperatures and monitoring whether they do, in fact, lose weight without having to exercise or change dietary patterns. The following is a selection of some BAT studies that throw some light on this subject.
A 1961 study 30 when individuals had prolonged exposure to cold, showed that they became resilient and stopped displaying shivering thermogenesis, indicating that other mechanisms were being recruited.
In 2009, four separate studies 31323334 indicated clearly that BAT was present in a significant number of adults and that there was a correlation between its presence and activity related to indices of healthy metabolism.
In 2010, a study 35 showed that there was an inverse correlation between BAT activity and between obesity, diabetes and ageing – that is, the more active BAT was, the less obesity, diabetes and ageing was seen.
Naturally, up to this point, the relationship was one of correlation and no causal mechanism had been established. However, researchers were very interested in finding out more about the capacity and activity of human BAT as a therapeutic means of treating the various metabolic consequences of obesity. The majority of the consequent studies focused on this BAT adaptive thermogenesis response by exposing volunteers to cold.
A 2011 study 36 exposed individuals to short but intense cold (e.g. immersing a limb in ice-cold water). Whilst they showed that this does indeed increase energy expenditure, it’s a method that fails completely to correspond with day-to-day experience and is impossible to sustain over time.
Additional research demonstrated that such extreme cold exposure was not necessary to stimulate sustained physiologic adaptive thermogenesis. It could be stimulated by even mild cold exposure as that controlled within normal (and bearable) climate-controlled buildings. This was shown in a 2010 crossover study 37 which looked at the effects of the adaptive thermogenesis response to minimal changes in environmental temperature. Healthy volunteers underwent two 12-hour periods in a whole room calorimeter (Metabolic Chamber) at 19 and 24 °c to monitor energy expenditure (EE). Results indicated that such minimal modulation of environmental temperature was sufficient to increase EE by around 6%. Might not seem much but, if projected over a 24 hour period, it would represent a drop of 100 kcal in an individual of between 70-80 kg.
In addition to burning extra calories, exposure to mild cold (with the resulting increase in non-shivering thermogenesis) was shown to be sufficient to drive an adrenergic response38 , which promotes lipolysis39 (with fatty acids being the preferred substrate in BAT depots) and increased postprandial glucose disposal. Additionally, the intervention generated an increase in cortisol 40 and a state of relative insulin resistance during fasting, which indicate an activation of the stress response. These, and other responses are shown in the adjacent table.
The researchers point out that, although the magnitude of this change may appear insignificant – only one fifth of the negative energy balance recommended to achieve sustained weight loss – it is relevant to note that, over a 1-year period (all things being equal), these differences would be equivalent to a 20-day fast and to a daily 30-min walk at a moderate pace.
A subsequent 2013 study 41 confirmed BAT contributes to energy expenditure (EE) in response to mild cold exposure – namely, 12-hour metabolic chamber exposure to either 19 or 24 ° C.
Two other 2013 studies showed, in the first case 42 , that a short-term, moderate (10 days acclimatisation with exposure at 17 ° C daily for 2 hours) cold exposure was sufficient to increase the quantity of BAT, and, in the second case 43 , that a longer period of time (6 weeks acclimatisation with exposure at 17 ° C daily for 2 hours) resulted in “significant fat mass reduction“- as shown in the following photos and chart:
BAT activation was shown to improve glucose homeostasis 44 and insulin sensitivity 45 in humans. Additional studies 4647 looked at BAT and the hormone FGF-21 (fibroblast growth factor 21 production). FGF-21 is a critical metabolic regulator that governs glucose and lipid (fat) metabolism and plays an important role in the treatment of metabolic diseases, such as T2D (type 2 diabetes) and obesity. In T1D (type 1 diabetes), FGF-21 also reduces blood glucose levels and prevents diabetic complications. It was demonstrated that BAT activation through cold exposure can up-regulate circulating FGF-21 in humans by 37%. FGF21 improves insulin sensitivity and glucose metabolism which may partially explain its longevity promoting benefits.
This offers hope for those with impaired insulin function who might benefit from BAT activation. And it’s not just those with clinically impaired insulin function, such as type 2 diabetics, who could benefit from this. Over time, even mildly elevated blood glucose levels in otherwise healthy non-diabetic humans are associated with other physiological damage. This has been shown to result in higher levels of the damaging AGE’s (advanced glycation end products – found in animal products, processed and fried/barbecued/roasted fatty foods), as well as damage to the brain, eyes, tendons, endothelial cells and the cardiovascular system 484950 .
In a longer 2014 study 51 over four consecutive months, environmental temperature was modulated overnight – 24 ° C (run-in period), (cold acclimatisation), 24 ° C (wash-out period), and 30 ° C (heat acclimatisation). After a month of exposure to mild cold (19 ° C ), BAT volume and activity almost doubled, but after a month of exposure to warm temperature (30 ° C), BAT activity was negligible. The researchers commented that: “Remarkably, the increase in BAT activity following the cold acclimatisation was accompanied by a significant increase in postprandial glucose disposal, but only during mild cold exposure.”
One study 52 looked at levels of irisin (a relatively newly discovered hormone) as a result of both intense exercise and cold exposure. Irisin is nicknamed the “exercise hormone” since it’s released during moderate aerobic endurance activity and is known to be an anti-obesity and anti-diabetes hormone that regulates fat tissue and blood sugar, improving insulin sensitivity, bone quality/quantity 5354 , and building lean muscle mass. In essence, irisin is thought to help reduce obesity by converting white fat to brown fat 55 . Being that irisin is released by muscles during physical exercise 56 , if cold-exposure also releases irisin, then perhaps the metabolic benefits of such exposure would be similar to those when irisin is released through exercise. And, indeed, this study demonstrated that this appears to be the case.
And irisin has other interesting effects. A study 57 on the reasons why healthy centenarians are healthy noted that they tend to have increased serum irisin levels, whilst irisin levels were significantly lower in younger patients with myocardial infarction58 . So, although somewhat an aside to the main thrust of this blog, such findings are likely to prompt further research into the role of irisin in vascular disorders and life span extension.
Another hormone, adiponectin59 , has associations with both BAT activation and centenarians. It’s been shown 60 that when BAT is activated through cold exposure, adiponectin levels increase within just two hours, resulting in a 70% increase in circulating adiponectin in adult men. Interestingly, both male and female centenarians (as well as their offspring) have been found 61 both to have genetics which boost adiponectin and to have generally higher circulating levels of adiponectin. This suggests a further link between BAT activation and longevity – this time because of the increased production of adiponectin. Furthermore, these high concentrations of plasma adiponectin in centenarians were associated 62 with other favourable metabolic factors as well as with lower levels of C-reactive protein63 and E-selectin64 . It was mentioned earlier that BAT activation results in the production of FGF-21 – a hormone that improves insulin sensitivity and glucose metabolism. The latter benefits may explain why this hormone has been shown 46 to play a role in promoting longevity in humans.
In relation to fat and irisin, it was shown 65 that applying irisin to human preadipocytes (cells that can be transformed into different fat cells through the process of adipogenesis) , ordinary white adipocytes could be changed into beige adipocytes. This helps confirm the role of irisin as a myokine66 that can expand beige adipocyte mass, increasing the non-shivering thermogenesis capacity and, thereby, promoting a shift from inefficient and non-sustainable shivering thermogenesis to more efficient and sustainable non-shivering thermogenesis. In the following diagram, FGF-21 (fibroblast growth factor 21) promotes BAT’s activity of cold-induced non-shivering thermogenesis in humans.
All the above studies indicate both that human BAT is extremely plastic, and that activation via cold exposure is necessary to generate a significant metabolic response.
So, merely reducing the environmental temperature in your home could help to lose some body weight (represented by an additional energy expenditure of around 100 kcal) without actually undergoing exercise or changing one’s dietary habits. However, the amount of body fat you could lose through undergoing even colder and, consequently, more uncomfortable temperatures is something that I can’t imagine many people wanting to opt for as a weight-loss method.
Of course, integrating a bit of low temperature “therapy” might reduce one’s heating bills. And, of course, there is another weight-loss method associated with temperature modulation – namely, sweating your socks off in a sauna, albeit really just water that you’ll lose, and you’ll put the weight back on pretty soon afterwards when you rehydrate.
However, there is another simple non-exercise/non-dieting weight-loss method which is similar in effect to turning down the thermostat – namely, something called a standing desk. A standing desk is simply a matter of raising the height of one’s table (and hence the computer , book or paperwork thereon) and standing instead of sitting. Interestingly, this method has been shown 67 to increase calories burnt (in this case in young schoolchildren):
Another study 68 found that standing burned an extra 0.15 calories per minute, on average, compared with sitting. Men burned an extra 0.2 calories per minute while standing, which was twice as much as women, who burned an extra 0.1 calories. This was because men they typically have more muscle mass than women. This would mean that a person weighing around 63 kg (140 pounds/10 stones), replacing sitting with standing for six hours a day would burn an extra 54 calories per day.
Naturally, pharmaceutical companies may well try to come up with a “magic pill” that will stimulate BAT activity without the need for subjecting oneself to cold temperatures – maybe an injection or pill to stimulate BAT activity without having to ensure cold temperatures; but experience teaches us that most of these pharmaceutical wonder cures have unpleasant side effects and rarely prove as effective as their manufacturers initially claim.
So, whether of itself, or even when combined with another simple non-exercise/non-dietary change weight-loss method, it would seem that the benefits are interesting, though not comparable with the weight-loss benefits of a combination of exercise and eating a low-fat plant-based diet.
References & Notes
Adipocytes are cells specialised in fat storage and are found in connective tissue. [↩]
PET stands for positron-emission tomography (PET) and is a nuclear medicine functional imaging technique that is used to observe metabolic processes in the body as an aid to the diagnosis of disease. FDG stands for fludeoxyglucose, an analogue of glucose – the biologically active tracer molecule chosen for this type of scan. [↩]
In response to a stressor, the sympathetic nervous system orchestrates what you familiarly call the fight-or-flight response. It increases muscle blood flow and tension, dilates pupils, accelerates heart rate and respiration, and increases perspiration and arterial blood pressure. [↩]
Interscapular – of, relating to, situated in, or occurring in the region between the scapulae, shoulder blades [↩]
Supraclavicular – of, relating to, situated in, or occurring in the region above the scapulae, shoulder blades [↩]
Suprarenal – of, relating to, situated in, or occurring in the region above or anterior to the kidneys [↩]
Pericardial – of, relating to, situated in, or occurring in the pericardium, two thin layers of a sac-like tissue that surround the heart, which hold it in place and help it work [↩]
Paraaortic – of, relating to, situated in, or occurring in the region of the front of the lumbar vertebrae near the aorta [↩]
Paravertebral – of, relating to, situated in, or occurring in the region on each side of the vertebrae [↩]
Mediastinal – of, relating to, situated in, or occurring in the region in the middle of the chest that lies between the sternum (breastbone) and spinal column. The area contains vital organs including the heart, oesophagus, and trachea. [↩]
Andrenergic relates to nerve cells in which adrenaline, noradrenaline, or a similar substance acts as a neurotransmitter. The result of this is that there is a stimulation of the sympathetic nervous system (SNS), which is responsible for the fight-or-flight response, which is triggered for example by exercise or fear causing situations. This response dilates pupils, increases heart rate, mobilises energy, and diverts blood flow from non-essential organs to skeletal muscle. These effects together tend to increase physical performance/energy usage momentarily. [↩]
Lipolysis is the breakdown of fats and other lipids by hydrolysis to release fatty acids. [↩]
Cortisol helps to control blood sugar levels, regulate metabolism, help reduce inflammation, and assist with memory formulation. It has a controlling effect on salt and water balance and helps control blood pressure. [↩]
Myocardial infarction is commonly known as a heart attack, and occurs when blood flow decreases or stops to a part of the heart, causing damage to the heart muscle. The most common symptom is chest pain or discomfort which may travel into the shoulder, arm, back, neck, or jaw. [↩]
Adiponectin is a protein hormone that is produced by fat cells. Its physiological effects include the reduction of inflammation and atherogenesis (the formation of fatty deposits in the arteries) and enhancement of the response of cells to insulin. [↩]
High C-reactive protein (CRP) levels in your blood indicate inflammation in your body, possibly indicating an infection or other condition. [↩]
E-selectin is also associated with inflammation, mediating leukocyte rolling (adhesion) on activated endothelial cells at inflammatory sites. It may also support tumour cell adhesion during hematogenous metastasis (cancer spread) and may play roles in angiogenesis (cancer development) and haematopoiesis (production of blood cells). [↩]
Oh the scandal! The outrage! Grass-eaters winning a competition that should be dominated by pies filled with traditional steak and kidney, bacon and egg, pork and venison? And, to top it all, taking place in the hallowed heart of pork pie heaven, Melton Mowbray – the home of the classic pork pie.
For the sensitive souls (and taste buds) of the noble omnivore, this egregious affront to human taste and dignity comes far too soon on the back of Greggs’ launch of their ridiculously successful vegan sausage roll 1 . So successful, indeed, that it’s been credited as the cause of the 7% rise in the company’s share value 2 .
The vegan “pie” was produced by a company called Jon Thorner’s of Somerset 3 . As if it wouldn’t be so bad winning just one prize, they ended up winning a total of three awards at the recent 2019 British Pie Awards 4 for their Curried Sweet Potato & Butternut Squash, namely: “Best in Class”, “Best Producer” and “Supreme Pie Champion 2019”, beating 886 other competitors 5 at the contest in Melton Mowbray, Leicestershire 6 .
The leading chef, Richard Corrigan 7 , has blasted this butternut squash thing “a disgrace”. And, surely, the opinion of this Michelin-starred chef should be honoured and respected when he calls it a “pie in the sky”. All sane gastronomes will be relieved when he promises to make his “pig’s feet and black pudding and Swede pie” the next prize winner. 8
That’ll show those lily-livered lentil lovers!
While being interviewed by the Telegraph 9 , this bastion of butchery, who has proved his credentials as an arbiter of taste by having cooked for the Queen not once, but twice – showed how deeply affected he was by this culinary onslaught by uttering: “Please, please I’m going to cry.”
And, in support of the moderate and fair majority of people, he reminded us all of what proper food should be: “Pies are supposed to be filled with the most delicious morsels of steak and liver and kidney, with the jelly and little pieces of fat in the middle delicately dripping onto your tongue.”
As though we’ve not had enough of populist nonsense – what with Brexiteers bandying around such outdated words like “democracy” and “national pride”. But to now have this travesty inflicted upon our already bowed and bruised heads by…one can hardly bear to say the word…v e g a n s.
As Chef Corrigan explains: “The oldest culinary art form left in the world and the vegans have taken it away. It’s a disgrace…The millennials have taken over…We should all just retire now.”
Matthew O’Callaghan, chairman of the 2019 British Pie Awards, appears to have slipped from the comforting embrace of omnivore common sense when he claims: “This year’s Supreme Champion was outstanding and well deserving of the accolade. From its very appearance on the judging tray you knew it was going to do well and it didn’t disappoint when it was opened and tasted. This pie isn’t just for vegans, it’s a pie for everybody. With this award we can truly say that veganism is now entering the mainstream of British food.” 5
The scale of the challenge ahead from marauding lettuce-lovers should not daunt the still-virtuous veganphobic nation of true meat-eaters.
Even as the faceless hordes of herbivores lay siege to the once great nation and its noble gastronomic traditions, I am reminded of John of Gaunt’s spirit-raising words of encouragement, as he lay on his death bed in Act One of Shakespeare’s Richard II:
“This royal throne of kings, this scepter’d isle, This earth of majesty, this seat of Mars, This other Eden, demi-paradise, This fortress built by Nature for herself Against infection and the hand of war, This happy breed of men, this little world, This precious stone set in the silver sea, Which serves it in the office of a wall, Or as a moat defensive to a house, Against the envy of less happier lands, This blessed plot, this earth, this realm, this England, This nurse, this teeming womb of royal kings, Fear’d by their breed and famous by their birth, Renowned for their deeds as far from home, For Christian service and true chivalry, As is the sepulchre in stubborn Jewry, Of the world’s ransom, blessed Mary’s Son, This land of such dear souls, this dear dear land, Dear for her reputation through the world, Is now leased out, I die pronouncing it, Like to a tenement or pelting farm: England, bound in with the triumphant sea Whose rocky shore beats back the envious siege Of watery Neptune, is now bound in with shame, With inky blots and rotten parchment bonds: That England, that was wont to conquer others, Hath made a shameful conquest of itself. Ah, would the scandal vanish with my life, How happy then were my ensuing death!”
He may as well have been making this speech now, just as the lights are being extinguished in the finest meat and two veg eateries across our nation…
Now, I’m not claiming that the likes of Thorner’s vegan pie or Greggs’ vegan sausage roll are either ideal foods for optimal human health or what I would recommend as part of a WFPB diet – except maybe the very occasional “treat” to remind ourselves of what too much added salt and oil taste like. I mean, the name of my Greggs’ blog (“Greggs’ Vegan Sausage Rolls – Why Veganism Can Fail“) was not chosen for no reason!
However, the amount of venom spewed out by newspaper readers is somewhat over-the-top by anyone’s standards.
Such as some of those following the Telegraph article 9 :
“What’s the problem? They are made out of Vegans, aren’t they?”
“I can’t eat grass; animals can. I can eat animals.”
“Sorry, vegans. I only eat fatty pork pies, or pies with succulent chunks of cow floating in ale and gravy.”
“You can keep your veggie rubbish.”
“I’m with Mr Corrigan: if it’s “vegan” you can’t call it a pie. That would be an insult to the centuries of gloriously rich, meaty, aromatic, mouth-watering pies that have gone before. A non-meat snack for trendy neurotics, perhaps?”
“Meat is good and the majority of people will not succumb to this utter BS.”
“Also why salad lovers liberally apply dressing: because chomping on grass is not for humans it’s for ruminants. Cows eat the grass, we eat the cows, that’s the way the food chain works.”
“You do know you’re made of meat right? And when your vegan body starts to starve you start to digest it to survive. That will be the least of your problems.”
And if you think that trying to educate people about veganism is a bit of a challenge, try espousing the virtues of a non-SOS WFPB diet. You’d lose count of the toys thrown out of prams.