There is a common belief that taking omega 3 supplements will protect the heart. Alphalinolenic acid (ALA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) are the 3 main types of omega 3 fats found in the food we eat that we require in small amounts to maintain good health. ALA is found in nuts and seeds, and EPA and DHA, or “long-chain” omega 3 fats, are found in salmon and fish oils.
New Cochrane research suggests that increasing long-chain omega 3 or ALA probably does not affect body weight or fatness, and omega 3 supplements do not reduce the risk of heart disease, stroke or death.
“Omega 3 supplements have little or no heart or vascular health benefit according to Cochrane review“
Dr. Lee Hooper, Cochrane lead author, 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 good 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. The most trustworthy studies consistently showed little or no effect of long-chain omega 3 fats on cardiovascular health. On the other hand, while oily fish is a healthy food, it is unclear from the small number of trials whether eating more oily fish is protective of our hearts. 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, 143 people would need to increase their ALA intake to prevent one person developing arrhythmia. One thousand people would need to increase their ALA intake to prevent one person dying of coronary heart disease or experiencing a cardiovascular event. ALA is an essential fatty acid, an important part of a balanced diet, and increasing intakes may be slightly beneficial for prevention or treatment of cardiovascular disease."