Saturday

13


October , 2018
Omega 3 controversy
14:11 pm

Maneka Sanjay Gandhi


Every few years a company's marketing strategy becomes a hit and a new “superfood” is born. Currently, it is Macha tea which solves all problems including weight, diabetes, and rheumatism. It comes on the heels of quinoa, chia seeds, Leh berries, Brazil nuts, blueberries, turmeric, spirulina, goji berries, dark chocolate, red wine, coconut oil, extra virgin olive oil and, if you believe the Chinese, gelatine made from donkey skin.

Of these, the biggest marketing gimmick that has seduced millions of people for three decades is Omega 3 fatty acids made from fish oil. Especially from wild caught fatty fish such as tuna, mackerel or salmon. Many people take a daily omega 3 supplement in the belief that it is good for their heart. Sold as pills, capsules and oils  in supermarkets, pharmacies and everywhere else, these are the most popular type of supplement, with more than a quarter of people, who take any kind of supplement, choosing them. The market is estimated at 500 million pounds annually.

Omega 3 fatty acids were touted as miracle supplements that promoted brain health, protected against dementia and depression and rheumatoid arthritis, reduced symptoms of irritable bowel syndrome, reduced weight, increased cardiovascular health, and helped in cancer prevention. Each year the claims became more exaggerated: “Omega 3 fatty acids are essential for the functioning of the body, lowering fat levels in the blood, reducing blood pressure and stopping blood clots.” The main emphasis was on preventing heart attacks, heart disease and strokes.

Now we learn that this was another gimmick, like most of the ones listed above. While all of them are healthy foods, so are all vegetables, grains and fruit. Omega 3, sold over the counter supplements, has just made companies billionaires without having any effect on heart problems.

Omega 3 is a type of fat. Small amounts of omega 3 fats are essential for good health. The main types of omega 3 fatty acids are alphalinolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA). ALA is normally found in fats from plant foods, such as nuts and seeds (walnuts and rapeseed for instance). EPA and DHA, collectively called long chain omega 3 fats, are found in fatty fish, such as salmon and fish oils including cod liver oil. Omega 3 fats, it is believed, will protect against heart disease by reducing blood pressure or reducing cholesterol.

The Cochrane Library was founded in 1993. It was developed for up-to-date, systematic reviews of all scientific trials of health care, and is used by scientists and policy makers as high-quality, independent evidence to inform healthcare decision-making. Each Cochrane Review addresses a clearly formulated question and summarises the results of healthcare studies (controlled trials) and provides evidence on the effectiveness of healthcare interventions. 130 countries work together to produce credible, accessible health information that is free from commercial sponsorship and other conflicts of interest. Cochrane reviews are the international gold standard for high quality, trusted information.

A new Cochrane systematic review, published in the Cochrane Library, combines the results of seventy-nine randomised trials (including 25 deemed  highly trustworthy) involving 1,12,059 people. The duration of the follow-up ranged from one year to eight years. These studies assessed the effects of consuming additional omega 3 fat, compared to usual or lower omega 3, on diseases of the heart and circulation.

The studies recruited people, some healthy and others with existing illnesses from North America, Europe, Australia and Asia. Participants were randomly assigned to increase their omega 3 fats, or to maintain their usual intake of fat, for at least a year. Most studies investigated the impact of giving a long-chain omega 3 supplement in a capsule form, and compared it to a dummy pill. A few assessed whole fish intake. The ALA trials added omega 3 fats to foods and gave these enriched foods, or naturally ALA-rich foods such as walnuts, to people in the intervention groups, and usual (non-enriched) foods to other participants.

The Cochrane researchers have found that increasing long-chain omega 3 provides no meaningful effect or benefits. The risk of death from any of the above mentioned diseases remains the same. 

They found that taking more long-chain omega 3 fats (including EPA and DHA), primarily through supplements or fish oil, makes little or no difference to the risk of coronary heart deaths, coronary heart disease events, stroke or heart irregularities. In fact, long-chain omega 3 fats reduce HDL cholesterol (good cholesterol), which makes the heart vulnerable to disease, as HDL is known to protect arteries from damage.

Increasing long-chain omega 3, or ALA, probably does not affect body weight or fatness.

Cochrane lead author, Dr. Lee Hooper from the University of East Anglia, UK, said: “We can be confident in the findings of this review which go against the popular belief that long-chain omega 3 supplements protect the heart. This large systematic review included information from many thousands of people over long periods.  Despite all this information, we don’t see protective effects.”

“The review provides strong evidence that taking long-chain omega 3 (fish oil, EPA or DHA) supplements does not benefit heart health or reduce our risk of stroke or death from any cause. When we separated out the 25 studies that used the best methods, such as “blinding” the participants and the researchers to which group was getting the omega 3 and which the placebo, the effect of omega 3 on the outcomes was even weaker. This suggests that when we reduce the potential for bias in omega 3 trials, there is even more clearly no effect of omega 3 supplements.”

“It looks as though our belief in omega 3 supplements over all these years may have been driven by a few flawed studies and our own bias.”

“This systematic review did find moderate evidence that ALA, found in plant oils (such as rapeseed or canola oil) and nuts (particularly walnuts) may be slightly protective of some diseases of the heart and circulation. However, the effect is very small.”

This belief in the heart health benefits of omega 3 fat sprang from observations suggesting that the Inuits don’t suffer from heart disease because their diet is mainly fatty fish/cod liver oil, and two other trials suggesting the benefits of eating fish and of taking fish oil supplements. The companies making Omega 3 poured millions into advertising and hid the fact that follow-up studies from both research groups had negative results. In fact, in one of the studies, men with angina who were randomly assigned to take omega 3 supplements were at greater risk of “cardiac death” than those who weren’t assigned to take the supplement.

While the American Heart Association claimed that Omega 3 supplements were beneficial to people with, or at risk of , heart disease, the European Society of Cardiology refused to do so saying there was no evidence to justify the supplements. The WHO wanted to understand the health benefits of omega 3 fats, as it is updating its guidance on fats, and they commissioned the review.

The British Heart Foundation has backed the study and urged people to focus on healthy food rather than pills.

Stop wasting your money on fish oil supplements and spend the money on fresh vegetables. Fish won’t save you, but beans and berries might.

Full citation: Abdelhamid AS, Brown TJ, Brainard JS, Biswas P, Thorpe GC, Moore HJ, Deane KHO, AlAbdulghafoor FK, Summerbell CD, Worthington HV, Song F, Hooper L. Omega 3 fatty acids for the primary and secondary prevention of cardiovascular disease. Cochrane Database of Systematic Reviews 2018, Issue 7. Art. No.: CD003177. DOI: 10.1002/14651858. CD003177. pub3.

 

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