Although eating fish does confer some health benefits, there is growing evidence to suggest that the value of fish oil supplements is less sustained.
Oily fish like salmon, trout, and herring are great sources of omega-3 fatty acids, which are associated with protective effects on the heart.
Years of research studies have tested whether omega-3 fatty acid supplements such as fish oil are also beneficial.
This week, researchers who looked at heart surgery patients who took fish oil supplements before and after the procedure said taking the supplements didn’t seem to help patients heal better.
In the United States, researchers randomly assigned 1,516 heart surgery patients in the United States, Italy and Argentina to take one-gram capsules containing omega-3 fatty acids or a placebo olive oil before and after their intervention, such as valve replacement.
They hoped to reduce atrial fibrillation or postoperative flutter (AF), an irregular heartbeat that occurs in about one in three patients undergoing heart surgery.
“Our results provide no evidence that omega-3s in the short term[polyunsaturated fatty acids] supplementation provides clinically relevant antiarrhythmic effects in the acute setting of cardiac surgery, ”concluded Dr. Dariush Mozaffarian of the Harvard School of Public Health in Boston and his coauthors in the Journal of the American Medical Association.
Participants took fish oil capsules containing at least 840 milligrams of long-chain omega-3 polyunsaturated fatty acids (PUFAs), a prescription strength of the supplements.
Fish for supplements
The total number of days spent in the intensive care unit or in the coronary care unit was about the same in the two groups.
The study is the latest to question the benefits of supplements and fortification, an industry estimated at $ 25 billion worldwide in 2011.
“It may be something else in the fish that provides benefits, as the fish contains all kinds of minerals and other healthy ingredients,” said Dr Andreas Wielgosz, cardiologist in Ottawa and spokesperson. from the Heart and Stroke Foundation.
“It may be that when you eat fish, you are eating less saturated foods. The exact answer is not known, but what we can say is that the natural source is better than supplements.”
Two more research papers earlier this year found that supplements do not reduce heart attacks or strokes in people at high risk, and they do not prevent cognitive decline or dementia in healthy older people. .
Although the initial study on the benefits for the heart of fish oil capsules in the late 1990s showed a 45% reduction in sudden cardiac death, the use of drugs like statins has dramatically increased since then, said Ken Stark, professor of applied health sciences at the University of Waterloo who studies the metabolism of polyunsaturated fatty acids.
The use of medication may mask the benefits conferred by omega-3s.
“That’s not to say omega-3s don’t work,” Stark said.
People tend not to keep taking the supplements, depending on their blood levels, and dosages have been lowered over the past 20 years, he added.
“We’re suddenly giving 500 milligrams in some of these clinical studies when the Japanese are eating two grams a day.”
Stark’s lab research suggests that the anti-inflammatory properties of omega-3s could help treat or prevent arthritis or eye disease, although these ideas have not been tested in high-quality trials.
Flip in fish oil
Dr Hertzel Gerstein, of the Population Health Research Institute at McMaster University in Hamilton, warns that taking supplements instead of drugs such as statins or lowering blood pressure could cause indirect harm.
“If people take a drug that there is no good evidence for… [and] they are not taking proven drugs, so it can put them at risk. “
When omega-3 supplements were tested in clinical trials, they didn’t work, Gerstein said.
For the most part, omega-3 supplements don’t cause side effects, although some people complain of fishy odor or nausea when taking large doses, Gerstein added.
Janet Torge from Montreal was spending $ 250 per month on supplements recommended by a naturopath. Torge remembered reading that omega-3s are believed to help prevent dementia, so she added the supplements to her diet. But later, she ditched supplements to more closely monitor what she eats.
“I think the lesson is that you go with a healthy lifestyle, like the basics,” Torge said.
Gerry Harrington is Director of Public Affairs for Consumer Health Products Canada in Ottawa, which represents manufacturers, marketers and distributors of vitamins, dietary supplements and other health products.
“I think the challenge is for people to be able to put each individual study into context and realize that it is an ongoing process and that the miracle vitamin one year might be a lot less appealing next year.” , Harrington said.
Harrington acknowledged that the conflicting research results are confusing and frustrating for people trying to make healthy choices. He suggested that people talk to their pharmacist before taking any supplements.