Experts weigh the latest findings on heart health with fish oil

In the world of wellness, there are few things as mundane and confusing to digest as advice about vitamins and supplements and whether they have any benefit.

Research published last month in the journal BMJ Medicine looked at the risk-versus-benefit profile of fish oil on heart health, and suggested from a multi-year study that taking fish oil regularly may have some increase the risk of cardiovascular events, including atrial fibrillation and stroke, in people who are not at high risk.

In people who already had cardiovascular disease, researchers found that taking fish oil supplements had benefits and influenced the course of the disease.

Fish oil supplements are perhaps the most common type of omega-3 supplement that people can get without a prescription. They often come in capsule form, and people take them because other research has linked omega-3 intake to possible health benefits variety of health problemsincluding rheumatoid arthritis, cognition, and even things like ADHD. Recently, omega-3 supplementation has been linked to a reduction of anger.

But the fact that fish oil supplements may not be good for heart health in the general population is “not a new issue, just a new paper on the subject,” Dr. Andrew Freeman, a cardiologist at National Jewish Health in Denver, told CNET.

He added that over-the-counter fish oil supplements differ from the “highly purified” forms of fish oil, including Lovaza And Vasethat people can get on prescription from their doctor to lower their triglycerides. (High triglycerides contribute to cardiovascular risk.)

While the word on the benefits and risks of omega-3 supplements is far from final (this study had limitations, including the fact that people self-reported how much fish oil they took, so this study did not report dosages), it does raise questions that still conflict with recommendations for supplements in general. For example, the fact that they are not regulated for safety or effectiveness by the U.S. Food and Drug Administration and the fact that we must get most of our nutrients from food and diet.

Certain eating patterns that focus largely on plant foods rich in healthy fats, lean proteins, and some food-based fish oil sources (including diets like the Mediterranean diet) continue to be associated with positive health outcomes. These diets may be rich in omega-3 fatty acids and other nutrients, but replicating those benefits in supplement form has proven difficult.

Another important caveat is that people take supplements (including omega-3 fatty acids and fish oil) for reasons other than heart health. So whether you should take supplements depends on you, your diet, and your health goals, which can change over the course of your life.

“There is not much evidence for omega-3 supplements in general,” Doctor Navya Mysorea family physician in New York, said in an email. If someone is interested in adding one to their routine for any health issue, she said, it’s a good idea to check with a doctor before “making a personal decision for yourself.”

Read more: Omega-3 rich foods offer many benefits for the heart, hearing and overall health

What did the study find? Strengths and limitations

The BMJ Medicine study followed more than 400,000 participants aged 40 to 69 who took part in the UK Biobank study. They tracked their health events and reported lifestyle and dietary factors, including whether they regularly took fish oil supplements, their regular food consumption and more.

After years of research, researchers found that fish oil supplements were beneficial for people who already had heart disease. However, in the general population (i.e., people without heart disease), regular fish oil intake was associated with an increased risk of new heart disease and stroke.

Strengths of the study include that it is large and that it was able to track incident heart disease. Researchers also gathered details about some factors that can affect heart health, such as smoking, binge drinking and overall diet. However, it “did not account for behavioral changes in populations with different cardiovascular profiles,” the researchers wrote. It also cannot account for all of the health-influencing behaviors that can influence a person’s wellness choices, which are notoriously difficult to tease apart and pin down to a single cause or effect.

Additionally, most of the study participants were white, the researchers noted, so whether the same link can be drawn for people of other races is unknown from this study alone. And importantly, it didn’t take into account the dosage of fish oil people took or specific brands or types.

Who is this study interesting for?

The latest findings shouldn’t panic you and make you feel like your omega-3 or fish oil pills are heart problems in a bottle; as the study authors noted, more research is needed on the link between cardiovascular events and fish oil, and it builds on ongoing research into the extensive, intricate link between omega-3 fatty acids and various health benefits when they come in supplement form. For the general population at least, it is often contradictory or inconclusive.

According to Dr. Gregory Katz, a cardiologist at NYU Langone, this study alone is not enough to definitively break the argument about the benefits of fish oil.

“To change clinical practice, you can only see cause and effect with a randomized trial,” Katz said in an email. “A study like this doesn’t tell you whether the fish oil caused the irregular heartbeats.”

But, he said, “a number of clinical trials of high-dose omega-3 supplements have shown an increased risk of an irregular heartbeat called atrial fibrillation,” which increases the risk of stroke.

As for whether vegan or vegetarian omega-3 supplements would be better (supplements that consist of ALA instead of DHA and EPA), the evidence is also unclear, since ALA is a “precursor in the body to DHA and EPA, the active omega-3s,” Katz said. He added that the way it is converted into active omega-3s is not as efficient and may not be “as useful.”

So it all comes back to the same advice: get your omega-3s (and all other nutrients) from food when possible. If that’s not possible, talk to your doctor about whether starting a supplement or taking extra vitamins is appropriate. Because people may be interested in taking omega-3s for health reasons other than just heart health, talk to someone who understands your medical history so you can weigh your risks and benefits.

In a major review last updated in 2023, which looked at available studies on omega-3 fatty acids and omega-3 supplements for a range of health conditions, including heart disease, the National Institutes of Health Office of Dietary Supplements concluded that “consuming fish and other seafood as part of a balanced diet promotes heart health, especially when the seafood is consumed in place of less healthy foods.” But evidence for protective heart health benefits from supplements is stronger in people with existing diseases.

However, the latest findings do provide much-needed nuances for supplements.

“Not everyone is the same,” Freeman said of the latest fish oil study. “Not all drugs are the same, and what seems harmless isn’t always the same.”