In the journals
Taking a daily omega-3 fatty acid supplement might not reduce your chance of heart attacks or strokes if you already have heart disease or are at high risk for it, suggests a meta-analysis published online Jan. 31, 2018, by JAMA Cardiology.
The researchers compared 10 trials that included almost 78,000 people, approximately 47,000 of whom were men, with an average age of 64. Each trial involved at least 500 people who took daily doses of either an omega-3 fatty acid supplement or a placebo for at least a year. All participants had heart disease, had experienced a stroke, or were at high risk for these conditions.
After more than four years, there was no significant reduction in the rate of fatal and nonfatal heart attacks and strokes among the supplement group. Omega-3 fatty acids also showed no benefit among subgroups — for instance, people who had diabetes, had high cholesterol levels, or regularly used statins.
The researchers noted that the average daily dose was 1,000 milligrams, and more research is needed to see if higher amounts might be better. It is not known if getting omega-3s only from food like fatty fish might yield different results.
Also, while earlier studies have suggested that omega-3 fatty acid supplements could reduce the risk of a second heart attack, follow-up research has failed to confirm this.