Some seemingly conflicting research results can leave people confused about whether or not fish is a healthy option. A major reason for this confusion is we’re told fish oils contain omega-3 fatty acids which our bodies need to function properly. So if fish oils contain this vital ingredient, what’s the problem with tucking into a nice piece of salmon?
The issue is not whether the omega-3 in fish is of itself healthy or not, but whether we need to eat fish in order to get the omega-3 our bodies need.
Omega-3 (alpha-linolenic acid or ALA and also written as n-3) are long-chain essential polyunsaturated fatty acids. They are called “essential” because our bodies can’t make them. Therefore, it’s essential that we get them from food.
ALA is a precursor for the production of EPA and DHA.
EPA and DHA are predominantly found in fish and that’s why they are often referred to as marine omega-3’s.
Those who don’t eat fish can find ALA in whole grains, leafy green vegetables, soy, seeds and nuts (particularly walnuts, flaxseeds, and chia seeds). But the body then has to get on with the job of converting it into EPA ad DHA – some ALA is used for energy production, so only a limited amount is converted into EPA and DHA.
Much debate goes on, therefore, about whether those people who don’t eat “ready-made” EPA and DHA from fish are able to get sufficient ALA in their diets to produce the EPA and DHA that the body requires.
At this stage, discussions about which source is best usually ends up with a reductionist downward spiral, normally focusing solely on an isolated process or nutrient – in this case omega-3. The forest disappears behind the tree.
The more specific issues of plant-based omega-3 quality and quantity will be covered in depth in further articles.
For the time being, I just want to suggest that we would do better by viewing this whole subject from a broader perspective so that we can see the bigger picture.
Over 100 years worth of peer-reviewed published studies have demonstrated links between eating animal products and a range of diseases, including diabetes, obesity, heart disease and cancer. At the same time, whole plant foods have been shown to have quite the opposite effect – acting as natural protection against such diseases.
Added to this are the not-inconsiderable concerns about pollutants in fish and the dangers associated with fish oil supplements. So, why bother killing our fishy friends for something we can get from plants?
The amount of phytonutrients in fish oils is minimal when compared to those found in whole plants. And when you eat whole plants, rather than the oils that can be fragmented from them – almond oil from almonds, olive oil from olives – there are none of the negative side-effects associated with consuming oils – whether derived from animals or plants.
This is why we benefit from looking at the common denominator within nutritional research – namely, that what comes out on top every time is the consumption of more whole plants.
As Professor T Colin Campbell points out repeatedly, single mechanisms can give us clues about the inexpressible complexity of the biochemical systems and interrelations within the human body, but these single elements can never provide an overview of the ‘big picture’ of human health. This is something that can only be appreciated by drawing in data from a wide-range of sources. Amongst these are:
- Large-scale observational studies over time on whole populations – such as the 800 million Chinese forming the basis of The China Study, and the half million Europeans forming the basis of the EPIC study.
- Smaller-scale, controlled, interventional studies – such as Dr Dean Ornish’s work on prostate cancer, Dr Caldwell B Esselstyn’s work on heart disease, and Dr N Barnard’s work on diabetes.
- Highly specific and detailed research to find and explain the mechanisms that might produce the results seen in the above studies – such as Professor T Colin Campbell’s work on the role of animal protein in cancer initiation, promotion & progression, and Dr David Jenkins’ work on glycaemic load.
If any one of these three approaches were producing contrary findings to the other two, then there would be room for serious doubt; but all three point in exactly the same direction – that a WFPBD with no added salt, oil or sugar is consistently shown to be the healthiest diet for the human body, both in terms of morbidity and mortality.
So where does this leave the omega-3 in fish?
Well, let’s just leave it in the fish…
Dr John McDougall – Confessions of a Fish Killer. https://www.drmcdougall.com/misc/2007nl/jun/confessions.htm
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