The Omega-3 Pioneer: Why DHA is essential for good health
They call him the godfather of the Omega-3 Movement. Dr Jorn Dyerberg first discovered the health benefits of omega-3 polyunsaturated fatty acids in the early 1970s, following a landmark study of the inhabitants of a small island in Greenland known as Unknown Island. In a Health365 Exclusive, we spoke to Dyerberg about the importance of omega-3, and why omega-3 DHA may be more important for your health than EPA and ALA.
Dyerberg and the team of Danish researchers ventured by dog sled to the tiny island community to study why only 5.2% of the Inuit population were dying from cardiovascular disease.
“The basis was that the Danish Eskimos living in Greenland had a far lower rate of coronary heart attacks than the Danes in spite of a fatty diet and when examining that diet we found that the reason could be due to a huge difference in fatty acid content.” recalls Dyerberg.
The research group’s initial paper was accepted by The Lancet in 1971 and has gone on to become a Nutrition Classic, resulting in more than 25,000 further research papers on omega-3 fatty acids.
The group discovered that the blood lipid levels of the Greenland Inuit were favourable for a healthy heart when compared to the Danes and Americans, but not to an extent that could explain why the incidence of heart disease was so much lower. It had to mean that the sorts of fatty acids they were eating were making the difference. From this hypothesis, the researchers went on to find that Eicosapentaenoic acid or EPA was an anti-clotting agent, which may be responsible for the lower incidence of heart disease.
Now more than 40 years after that initial study, researchers have gone on to definitively show the following favourable effects of both omega-3 EPA and docosahexaenoic acid (DHA) in more than 13,000 human studies.
- Anti clotting EPA
- Anti depressive effect EPA
- Lower blood triglycerides EPA and DHA
- Anti-inflammatory DHA and EPA
- Protection of vision DHA and EPA
- Lower blood pressure DHA
- Cognition/Dementia DHA
Dr Dyerberg describes omega-3 EPA and especially DHA as “essential for our brains from cradle to grave.”
Food Sources of Omega-3
The best food sources of omega-3 fatty acids are seafood. Vegetarian sources of omega 3, such as walnuts, flaxseed oil and green leafy vegetables do not contain EPA or DHA. They contain the third type of omega-3, alpha-linolenic acid (ALA) and whilst ALA can be converted by the body into EPA and DHA, the conversion to EPA is poor, and the conversion to DHA is so low as to be almost non-existent.
“Overall, ALA appears to be a limited source of longer chain omega-3 PUFA in humans. Thus, adequate intakes of preformed long chain omega-3 fatty acids, in particular DHA, may be important for maintaining optimal tissue function” Reprod. Nutr. Dev. 45 (2005) 581–597
The recommended dose for omega-3 is anywhere between 400 – 600 mg a day. The Australian Heart Foundation recommends that you eat three servings of oily fish a week to reach this amount, however the majority of Australians do not meet this recommendation.
As a quick guideline here is how you can eat your recommended dose of DHA:
- 150gms of salmon, mackerel or trevalla three times a week
- 150gms of squid or oysters three times a week
- 300gms of dory, flounder, snapper, cod or bass three times a week
- 1 calamari oil tablet daily
Can’t I just eat fish to get my omega-3 EPA and DHA?
Many people insist that supplementing their diets is simply not necessary if they are eating enough fish. This may be true for those who are eating more than the recommended amount of fish each week, but the majority of Australians simply are not.
When pressed for detail on how he gets his daily omega-3s, Dr Dyerberg comments that he enjoys a fish meal one to two times per week, but still supplements his diet with a 1000mg omega-3 supplement each day. He goes on to recommend people find an omega-3 supplement with a high DHA to EPA ratio. “If you look at the body and see it through the body cells, there is far more DHA than EPA for the simple reason that DHA has far more function that EPA,” he explains.
So which supplements are richer in omega-3 DHA? We’ve broken it down to look at the most common omega-3 supplements below:
- Calamari oil – 470mg/g of DHA
- Algal – 350mg/g of DHA
- Fish oil– 120mg/g of DHA
- Flaxseed – 0mg/g of DHA
Fish Oil, Krill Oil, Now Calamari Oil?
Fish oil is still the most studied of all the available options, however it is not the source of the EPA or DHA that counts, it is the overall content of each of EPA and DHA in the supplement that matters.
“From a sustainability point of view, and also from the composition, it (calamari oil) is a favourable source in my eyes.” says Dr Dyerberg.
Leif Kjetil, the CEO of Pharma Marine, the company that pioneered the production of calamari oil agrees. “Calamari oil supplements contain more omega-3 than fish oil and krill oil combined. The calamari oil now available in Australia has the highest content of DHA of all supplements in the market.”
Wherever you decide to get your omega-3 fatty acids from, it is undoubtedly one of the most important supplements known for human health.
From his years of research and study Doctor Dyerberg knows this to be true. “From a disease point of view, or from an evolutionary point of view, they are good for your brain (from before you are born to old age); they are good for your heart from your 20’s to your 80’s; they are good for your eyes; they are good for inflammation.”