Omega-3 fatty acids, hailed by some for properties said to enhance heart health, were found to have no effect in reducing the risk of stroke, heart attack or death, according to a study released Tuesday.
The study, which followed nearly 70 000 patients at a hospital in Greece who were given supplements of omega-3 polyunsaturated fatty acids, is published in the September 12 issue of the Journal of the American Medical Association (JAMA).
Researchers said patients at the University Hospital of Ioannina did not show a statistically significant reduction in death or heart illness, and questioned whether omega-3 should be administered proactively when trying to optimize a patient's heart health.
"Our findings do not justify the use of omega-3 as a structured intervention in everyday clinical practice or guidelines supporting dietary omega-3," said Evangelos Rizos, chief author of the study.
After examining 20 studies comprising a total of 68 680 randomised patients, the researchers said there were 7044 deaths, 3993 cardiac deaths, 1150 sudden deaths, 1837 heart attacks, and 1490 strokes.
An analysis of those figures indicated no "statistically significant" association with all-cause mortality, cardiac death, sudden death, heart attack, and stroke when all supplement studies were considered.
Health professionals, backed by a number of clinical trials, for years have touted the health benefits of omega-3, but the authors noted that other studies have failed to support those health claims.
The report in JAMA noted that some national regulatory agencies in Europe have approved the administration of omega-3 supplements to reduce the risk of heart attack or stroke.
The report said it is possible that studies showing some heart health benefit from taking omega-3 fatty acids "may be due to their ability to lower triglyceride levels, prevent serious arrhythmias, or even decrease platelet aggregation and lower blood pressure."
The researchers concluded that more research is needed, including "an individual patient data meta-analysis... to refine possible associations related to, among others, dose, adherence, baseline intake, and cardiovascular disease risk group."