In contrast to most different dietary supplements, fish oil has been rigorously studied, mentioned Dr. JoAnn Manson, a professor of drugs at Harvard Medical College. However the outcomes of these research have been blended, leaving researchers and medical doctors nonetheless debating whether or not fish oil is helpful for coronary heart well being. They’ve additionally revealed that taking fish oil is linked to a barely larger threat of creating atrial fibrillation, a sort of irregular heartbeat.

Right here’s the place the proof for each the advantages and dangers of fish oil stands immediately.

A boatload of research, however unclear advantages

After studying the dispatches from Greenland, researchers started individuals elsewhere on this planet and discovering, in examine after examine, that those that consumed fish no less than as soon as per week have been much less prone to die from coronary coronary heart illness than those that not often ate fish. In animal experiments, they discovered that fish oil helped maintain electrical signaling in coronary heart cells functioning correctly, mentioned Dr. Dariush Mozaffarian, a heart specialist and director of the Meals is Medication Institute at Tufts College.

“There was plenty of enthusiasm” about these findings, mentioned Dr. Christine Albert, the chair of the division of cardiology at Cedars-Sinai Medical Heart in Los Angeles. And it was pure to hope that folks would possibly have the ability to reap the identical advantages from taking fish oil in complement kind, she added.

However most scientific trials of fish oil capsules have reported no discount in demise from coronary heart illness or in whole cardiovascular occasions like coronary heart assault and stroke. That was the discovering of a 2018 meta-analysis combining the outcomes of 10 omega-3 trials that included almost 78,000 individuals. Equally, researchers reported no total coronary heart well being advantages of omega-3s in a 2018 trial of greater than 15,000 adults with Kind 2 diabetes adopted for a median of seven years; in a 2019 trial of greater than 25,000 adults 50 and older adopted for a median of 5 years; and in a 2020 trial of a excessive dose of omega-3s examined in additional than 13,000 individuals vulnerable to heart problems.

“One after one other of those research confirmed completely no advantages,” mentioned Dr. Steven Nissen, a heart specialist at Cleveland Clinic, who led the 2020 trial. (One trial, revealed in 2018, did present a hanging advantage of a excessive dose of the omega-3 EPA. But it surely has been extensively criticized for utilizing mineral oil, which can improve the chance of coronary heart illness, because the placebo, Dr. Nissen mentioned.)