Once again, recent studies found that eating real food (fish) is associated with health benefits, but taking a supplement (omega-3) isn't. Similar findings about fish versus omega-3 fatty acid supplements have also been found in other studies. Fish contains omega-3 fatty acids and many other nutrients - more than are found in supplements.
The first study is a Cochrane review of studies already done. The review provides good evidence that taking long-chain omega 3 (fish oil, EPA or DHA) supplements does not benefit heart health or reduce risk of stroke or death from any cause. In other words, people take the supplements believing it helps heart (cardiovascular) health - but the evidence isn't there.
On the other hand, a large study of people living throughout the US and followed for 16 years found an association with higher fish consumption and lower risk of early death, and death from cardiovascular disease. Additionally, in men - those eating the most fish (as compared to those eating the least) had a lower risk of death from cancer, respiratory disease, and liver disease, and in women - lower risk of death from Alzheimer's disease. However, eating fried fish didn't have those health benefits. The group eating the most fish had 8 oz or more fish per week, while the group having the least had less than 2 oz. per week.
From Science Daily: Omega 3 supplements have little or no heart or vascular health benefit
New evidence published today shows there is little or no effect of omega 3 supplements on our risk of experiencing heart disease, stroke or death.
Omega 3 is a type of fat. Small amounts of omega 3 fats are essential for good health, and they can be found in the food that we eat. 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 are rich sources). EPA and DHA, collectively called long chain omega 3 fats, are naturally found in fatty fish, such as salmon and fish oils including cod liver oil.
Increased consumption of omega 3 fats is widely promoted globally because of a common belief that that it will protect against heart disease. There is more than one possible mechanism for how they might help prevent heart disease, including reducing blood pressure or reducing cholesterol. Omega 3 fats are readily available as over-the-counter supplements and they are widely bought and used.
A new Cochrane systematic review, published today in the Cochrane Library, combines the results of seventy-nine randomised trials involving 112,059 people. These studies assessed effects of consuming additional omega 3 fat, compared to usual or lower omega 3, on diseases of the heart and circulation.
The Cochrane researchers found that increasing long-chain omega 3 provides little if any benefit on most outcomes that they looked at. They found high certainty evidence that long-chain omega 3 fats had little or no meaningful effect on the risk of death from any cause. The risk of death from any cause was 8.8% in people who had increased their intake of omega 3 fats, compared with 9% in people in the control groups.
They also found that taking more long-chain omega 3 fats (including EPA and DHA), primarily through supplements probably makes little or no difference to risk of cardiovascular events, coronary heart deaths, coronary heart disease events, stroke or heart irregularities. Long-chain omega 3 fats probably did reduce some blood fats, triglycerides and HDL cholesterol. Reducing triglycerides is likely to be protective of heart diseases, but reducing HDL has the opposite effect. The researchers collected information on harms from the studies, but information on bleeding and blood clots was very limited.
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.
From Science Daily: Fish consumption may prolong life
Consumption of fish and long-chain omega-3 fatty acids was associated with lower risks of early death in a Journal of Internal Medicine study.
In the study of 240,729 men and 180,580 women who were followed for 16 years, 54,230 men and 30,882 women died. Higher fish and long-chain omega-3 fatty acid intakes were significantly associated with lower total mortality. Comparing the highest with lowest quintiles of fish intake, men had 9% lower total mortality, 10% lower cardiovascular disease mortality, 6% lower cancer mortality, 20% lower respiratory disease mortality, and 37% lower chronic liver disease mortality, while women had 8% lower total mortality, 10% lower cardiovascular disease mortality, and 38% lower Alzheimer's disease mortality.
Fried fish consumption was not related to mortality in men, whereas it was associated with increased risks of mortality from all causes, cardiovascular disease, and respiratory disease in women. Long-chain omega-3 fatty acid intake was associated with 15% and 18% lower cardiovascular disease mortality in men and women, respectively, when comparing the highest and lowest quintiles.