Omega-3s are a group of polyunsaturated fatty acids that perform key functions in the human body.
They are part of the body’s cell membranes and play a crucial role in the production of hormones, which later control blood clotting and the elasticity of artery walls.
These fats are particularly important because, unlike other types of fat, the body cannot produce them on its own.
Instead, the body needs to get them from food. Omega-3 can be found in fish, nuts, oil, and flax seeds, as well as green, leafy vegetables.
Because of their fundamental role in the good functioning of the human body, omega-3s are believed to have a variety of health benefits, particularly in regards to heart disease. The fats seem to prevent arrhythmias by keeping the heartbeat at a steady pace, lowering the blood pressure, and improving the functioning of blood vessels.
Do omega-3 supplements benefit the population at large and can they be used to prevent heart disease?
To answer this question, the American Heart Association (AHA) reviewed several studies that investigate the benefits of omega-3 dietary supplementation and published a science advisory to report on the findings.
The writing committee was chaired by Dr. David Siscovick and the recommendations were published in the AHA’s journal Circulation.
Supplements may not be needed
The advisory group analyzed several randomized controlled trials that assessed the preventive potential of omega-3s on cardiovascular disease, as well as the effect of fish oil supplements on heart attacks, stroke, coronary heart disease, atrial fibrillation, and other conditions.
The reviewed studies were published since 2002. The advisory also analyzed two studies published before that year.
The trials considered for the advisory focused on the use of supplements, but not on omega-3 intake directly from food. They investigated the benefits of taking around 1,000 milligrams of omega-3 daily.
The writing committee concluded that treatment with omega-3 supplements is “reasonable” for patients who have experienced a heart attack or heart failure.
However, the review did not find sufficient evidence to support the use of omega-3 supplements as a preventive measure against heart disease in the general, healthy population.
“We cannot make a recommendation to use omega-3 fish oil supplements for primary prevention of cardiovascular disease at this time,” said Siscovick, senior vice president for research at The New York Academy of Medicine. “People in the general population who are taking omega-3 fish oil supplements are taking them in the absence of scientific data that shows any benefit of the supplements in preventing heart attacks, stroke, heart failure, or death for people who do not have a diagnosis of cardiovascular disease."
Significance of the report
The advisory’s recommendations are particularly significant given that more than 18 million adults in the United States said that they were taking omega-3 fish oil supplements in 2012, according to a study referenced by the authors.
The chair of the writing group explained that the new findings confirm previous recommendations made by the AHA in a scientific advisory they published in 2002.
"Scientific findings from the past two decades that focused on the prevention of cardiovascular diseases continue to show that among people who are at risk of dying from heart disease, the potential benefit of omega-3 fish oil supplements is still useful for people who have had a recent heart attack, which is consistent with the 2002 statement," Siscovick said.
The chair also commented on how the advisory affects healthcare professionals.
"Physicians should use this advisory as a guide to make decisions on whether omega-3 fish oil supplements might be appropriate for some patients,” Siscovik added. “The advisory concludes that supplementation with omega-3 fish oil may benefit patients with specific, clinical, cardiovascular disease indications, including patients with a recent prior heart attack and heart failure.”