Should I Alkalise My Body?

Some foods are acidic and others and alkaline. There’s been quite a bit of concern in some areas of the media, and even in nutritional circles, about the need to put effort into alkalising your body. This is because it’s claimed that if don’t take action to stop our bodies from becoming acidic, then we become more prone to a wide range of diseases, including cancer. But how much of this is based on solid research and how much is based on thin air?

You need to supplement your diet?

The idea is that we should take great care to eat only alkaline-forming foods and to avoid all acid-forming foods. All well and good but, in addition to this, we’re encouraged to take alkalising supplements which can contain several alkalising compounds such as:

  • sodium bicarbonate (baking soda) – something to be pretty cautious about doing 1
  • potassium hydroxideditto 2
  • sodium hydroxideditto  3
  • lemon juice powder
  • inulin
  • potassium citrate
  • calcium citrate
  • magnesium citrate
  • bamboo powder
  • cherry powder
  • the list goes on…
Just a handful of the wide range of (often v. expensive) alkalising supplements on the market.

The pH scale

Acidity and alkalinity are measured using the pH scale, which runs from 0 to 14.

  • 0 is very acidic
  • 7 is neutral
  • 14 is very alkaline

We’ve already looked at some of the benefits that research has uncovered about eating a largely alkaline diet 4 5 , but this has been in relation to eating a WFPB diet, and not taking questionable supplements or trying to raise alkalinity levels in an aggressive manner. But what’s wrong with trying to raise alkalinity throughout our bodies?

Our bodies have ‘compartments’

Different parts (or compartments) of our bodies have different natural pH levels. For instance:

  • stomach – pH of around 2 at rest and between 4 or 5 after a meal
    • amongst other negative effects, forcing the stomach to become more alkaline has been shown 6 to result in less iron absorption from our food
  • intestines – there are naturally varying pH levels (shown to be essential for health of our gut microbiome 7 ):
    • duodenum – pH of around 6
    • ileum – pH of around 7.4
    • caecum – pH of around 5.7
    • rectum – pH of around 6.7

  • vagina – pH of around 4.5  (lactic acid-secreting bacteria have been shown to be essential to prevent infections such as Candida albicans (thrush), which would develop in a neutral to alkaline environment) 8 9

And since the above is just a sample of the different pH levels required throughout the body, it should be clear that it may be unwise to try to ‘force’ alkalinity throughout the system.

Indeed, it’s not just a matter of being unwise to do so, it can be fatal.

The average pH level of our blood is strictly controlled so that it remains between a pH of 7.35 and 7.45, and our bodies have various complex and powerful mechanisms to ensure that this pH homeostasis is maintained.

However, if something overwhelms the ability of these ‘buffering’ mechanisms to do their job (such as introducing powerful alkalising supplements into your body or eating ), so that the blood pH rises above 7.7 (too alkaline), there’s one simple outcome – death. The same applies if unfortunate consequence occurs if blood pH drops below 7 (too acidic).

WFPB and pH level

So, how do we go about ensuring that our body is maintained at the optimal pH level?

We don’t. But our bodies do – if, that is, we eat an appropriate diet.

All animal products (including red/white meat, offal, fish, seafood, dairy – including cheese of course) and most processed foods have been shown to be acidic 10 while whole plant foods are mainly neutral to alkaline 11 . A WFPB diet, consisting largely of vegetables, fruits, legumes and whole grains is rich in fibre and resistant starch which ensure the gut microbiome have sufficient carbohydrate to make the short chain fatty acids which help maintain optimal pH in the colon. And you don’t need any of those expensive alkaline potions or pills to achieve this.

By eating a WFPB diet, you don’t have to think of yourself as “alkalising your blood”. Some plant foods are naturally more acidic/neutral/alkaline than others, but by eating a WFPB diet (particularly one without added salt, sugar or oil) , which is naturally balanced, you take the load off all the bodily mechanisms which would have otherwise have to work harder to maintain optimal pH should your diet consist of high acid-forming foods.

Kidney disease and pH level

There are huge and varied health benefits from eating a WFPB diet, and one of the clear benefits has been shown to be that the risk of kidney disease is greatly reduced, as compared with eating a diet rich in processed and animal foods 12 .

Final thoughts

As with so many aspects of human health, the simplest solutions are often the best. A non-SOS WFPB diet obviates the need for so many things that the media and even traditional nutritionists obsess about – such as protein-combining or calorie-counting. The same applies here: just eat the optimal diet and your body will maintain optimal pH level and hence optimal health – allowing you to find other things to worry about…


  1. Are Acid-Blocking Drugs Safe? Michael Greger M.D. FACLM October 29th, 2018 Volume 44 []
  2. NJH Hazardous Substance Fact Sheet – Potassium Hydroxide []
  3. ATSFR – Toxic Substance Portal – Sodium Hydroxide []
  4. Alkaline Diet – So What?! []
  5. Psoriasis & Eczema Cured by Alkaline Diet? Caution: Some Graphic Images []
  6. Gut. 1969 Mar;10(3):226-9. Role of gastric secretion in iron absorption. Jacobs A, Miles PM. []
  7. Fallingborg, J. (1999). Intraluminal pH of the human gastrointestinal tract. Danish Medical Bulletin, 46(3), 183-196. []
  8. Miller, E., Beasley, D., Dunn, R., & Archie, E. (2016). Lactobacilli dominance and vaginal pH: Why is the human vaginal microbiome unique? Frontiers in Microbiology, 7, 1936. []
  9. Vylkova, S., Carman, A., Danhof, H., Collette, J., Zhou, H., & Lorenz, M. (2011). The fungal pathogen Candida albicans autoinduces hyphal morphogenesis by raising extracellular pH. mBio, 3(e00055-11), 2. []
  10. Dr McDougall’s Nov 2003 Newsletter: How to Help a Meathead []
  11. Nutritionfacts: Alkaline Diet. []
  12. Mirmiran, P., Yuzbashian, E., & Bahadoran, Z. A. (2016). Dietary acid-base load and risk of chronic kidney disease in adults: Tehran Lipid and Glucose Study. Iranian Journal of Kidney Diseases, 3(119-125), 10. []