Fish oil supplements may be harmful, study finds. “Is it time to throw them away? the expert asks

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As an excellent source of heart-healthy omega-3 fatty acids, daily fish oil supplements are a popular way to reduce the risk of cardiovascular disease.

In the United States, approximately 20% of adults over the age of 60 frequently use these products in an effort to promote heart health.

However, a new study finds that regular consumption of fish oil supplements may increase, not reduce, the risk of first stroke and atrial fibrillation in people with good cardiovascular health.

Atrial fibrillation, also called atrial fibrillation or AF, is a type of arrhythmia or irregular heartbeat, which people often describe as a pounding or pounding in the chest.

“I see the title of this study as “Fish Oil Supplements: Is It Time to Throw Them Out or Not?” ” said cardiologist Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health in Denver.

“I say this because over-the-counter fish oil is very rarely recommended, not listed in any professional medical society guidelines, and yet it’s what most people take,” said Freeman, who does not did not participate in the study.

The study analyzed data from more than 415,000 people aged 40 to 69 participating in the UK Biobank, a longitudinal study of the health of people in the United Kingdom. Nearly a third of these people, followed for an average of 12 years, reported regularly consuming fish oil supplements.

For people without heart problems, regular consumption of fish oil supplements was associated with a 13% higher risk of developing atrial fibrillation and a 5% increased risk of having a stroke, according to the study published Tuesday in the journal BMJ Medicine.

Over-the-counter fish oil suffers from a lack of purity and consistency, as well as potential contaminants and heavy metals such as mercury contained in fish, Freeman said.

“Additionally, studies over the past decade have not been very positive regarding over-the-counter fish oil,” he added. “Fish oil had no benefit or, in some cases, could be harmful, such as in stroke and atrial fibrillation. So this is not new.

In fact, the new study found that people with heart disease when the research began had a 15% lower risk of going from atrial fibrillation to a heart attack and a 9% lower risk of going from heart failure to death when used fish oil.

Instead, prescription versions of fish oil, such as Vascepa and Lovaza, are used to counter risk factors such as high triglycerides, a type of blood fat, in people with a risk of cardiovascular disease, Freeman said.

“But even in highly purified prescription versions of fish oil, the risk of atrial fibrillation and sometimes stroke is also present and doctors are cautious about this,” Freeman said.

“Overall, I would say the days of people just going to the store and buying buckets of fish oil pills to keep them healthy should be over, but fish oil can still play a role in people who are already ill.”

When it comes to fish oil, “the devil is in the details,” said preventative Alzheimer’s neurologist Dr. Richard Isaacson, director of research at the Boca Neurodegenerative Disease Institute Raton, Florida. He did not participate in the study.

“First, we recommend testing omega-3 fatty acid levels – there are finger prick tests you can buy online that are accurate – and then you should continue testing. You don’t want to take fish oil if you don’t need it,” he said.

Isaacson recommends trying to get your omega-3 fatty acids from food sources and says sardines and wild salmon are the best sources because they are high in healthy unsaturated fats and low in mercury. Farmed salmon is not the best choice, he explained, due to impurities in the water in which it is raised.

Lake trout, mackerel, herring and albacore tuna are also good sources, he said. However, due to mercury levels in large fish like tuna, it recommends limiting albacore tuna consumption to twice a week.

Seaweed and algae are also good sources of omega 3 other than fish. Other plant-based options rich in omega-3 include chia seeds, edamame (soy beans), flax seeds, hemp seeds, and walnuts. But fatty acids come in a different form than those found in fish. Studies have shown that plant-based omega-3s may be more difficult to metabolize in people with higher levels of omega-6, another type of unsaturated fat found primarily in vegetable oils.

Prescription omega-3 fatty acids are superior to over-the-counter options, experts say, because of their purity and quality. But prescribed supplements can be expensive. For people who decide to purchase over-the-counter omega-3s, Isaacson gives this advice to his patients.

First, freshness of fish oil is essential, he said, adding that “buying from an online or retail supermarket, like Amazon or Costco, is not the best idea.”

“We recommend only purchasing it from a handful of reputable companies and their specific website,” Isaacson said. “The difference in quality between fish oil stored in a hot warehouse close to the expiration date and newly produced fish oil sent directly from the company and stored in the home refrigerator is night and day. ”

The U.S. Food and Drug Administration does not monitor the supplement industry to ensure that each vitamin or mineral actually contains what is stated on the label, nor does the federal agency verify whether the ingredients are contaminated by bacteria, heavy metals, pesticides, plastic. residues and other impurities.

However, some companies have taken on this role by testing various supplements and even some pharmaceutical products, so look for their labels on supplements before purchasing them. Experts say the nonprofit U.S. Pharmacopeia, or USP, sets the most widely accepted standards for supplements, but ConsumerLab.com and NSF International also conduct third-party testing.