I’ve written about the effects of omega-3 EPA/DHA on rheumatoid arthritis before but in this post I want to look at omega-3 EPA/DHA sources.
There are two essential fatty acid groups; linoleic acid (omega-6) and alpha-linolenic acid (omega-3). The essential alpha-linolenic acid (from plant sources) can be restructured in the body to produce the longer chained EPA and DHA fatty acids, EPA and DHA can also be obtained directly from algae and from animal sources, primarily fish.
Omega-3 ALA EPA DHA Sources
- The best sources of alpha-linolenic acid ALA are ground flax seeds, hemp seeds, chia seeds, walnuts and leafy greens.
- Plant sourced alpha-linolenic acid can be converted in the body to the longer chain EPA and DHA fatty acids. However, the efficiency of this conversion process varies from individual to individual based on gut health, age, medication intake and overall quality of diet etc. The efficiency of this conversion process is reduced by the high omega-6 intake of the standard UK (SUK) or American diet (SAD). The typical conversion efficiency of alpha-linolenic acid to EPA is fairly low and the subsequent conversion to DHA is even lower, particularly in men, leading some to conclude that EPA and DHA should be considered as conditionally-essential fatty acids.
- In theory, the best direct source of EPA and DHA is fish. However, because EPA and DHA are polyunsaturated fatty acids they are prone to oxidation and this process begins as soon as the fish is caught and killed (albeit slowly if the fish is cooled or frozen). By the time the fish is transported, displayed for sale, purchased then stored in refrigerator at home, and finally cooked, significant oxidation of EPA and DHA may have occurred. Also, fish are contaminated with environmental pollutants such as persistent organic pollutants and heavy metals. Although these contaminants are not as high as some media headlines would suggest, they are still a cause for concern since many of them accumulate in the body over time.
- Fish oil supplements (including the ubiquitous cod liver oil) are subject to many of the same oxidation risks as fish in terms of transportation and storage but in addition to these, fish oil supplements are subjected to an industrial refining process which usually involves exposure to high temperatures further promoting oxidation. Also, with fish oil supplements there’s no way for a consumer to be certain of the overall age of the supplement or its initial source, or in fact the actual amount of EPA and DHA contained within each supplement. And fish oil supplements can still suffer from the same contamination issues as fish (see: ‘3’ above).
- EPA and DHA supplements derived from algae which is shown to be bioequivalent to salmon sourced EPA and DHA may not contain the same contaminants as fish oil but I believe they are still subject to some of the same oxidation issues i.e. every algae-based omega-3 supplement I’ve tried smells rancid and ‘fishy’.
In conclusion; ground flax seeds, hemp seeds, chia seeds, walnuts and leafy greens are the best sources of alpha-linolenic acid and currently, algae derived omega-3 supplements appear to provide the safest source of EPA and DHA (if not rancid).
I believe it’s important to try to get all of our nutrients directly from whole plant foods and to avoid supplements where possible. The more experience and knowledge I gain in terms of nutrition and health (particularly in relation to treating rheumatoid arthritis) the more I try to avoid taking supplements.
These days I believe that supplements only serve two purposes; either to correct a nutritional deficiency in the short term until the diet can be brought up to scratch, or to be used as a therapeutic drug. For example a vitamin D3 supplement could be used to correct a deficiency during winter months, and an omega-3 supplement can be used in a drug-like fashion to reduce inflammation in rheumatoid arthritis (although this wouldn’t be a permanent solution).
A final thought. Omega-3 fatty acids obtained from food are essential for good health and provide many benefits by supporting brain function, immune system function, skin health, psychological health and so on. However, taking ‘supplemental’ omega-3 (with a couple of exceptions) has not proven to be particularly beneficial and in some cases can potentially be harmful to health. We can increase our omega-3 absorption from food by reducing our omega-6 intake (by removing refined oils and fats, and junk food) and by adding some turmeric to meals containing omega-3 rich foods such as leafy greens, flax seeds and hemp seeds.
Hemp and Fish Oil images are public domain