The supplement considered healthy for the heart: study finds link to increased risk

A broad study published in the medical journal BMJ Medicine is reigniting the debate surrounding one of the most popular dietary supplements in the world. Researchers followed more than 415,000 people for about 12 years and examined the link between regular use of fish oil supplements and cardiovascular diseases. The results showed that in people who were cardiac-healthy at the beginning of the study, taking the supplement regularly was linked to a 13% increase in the risk of developing atrial fibrillation and a 5% increase in the risk of stroke.

Fish oil contains omega-3 fatty acids, and for years it has enjoyed a reputation as a supplement that may help maintain heart health. For this reason, many people take a capsule daily even when they do not have heart disease or a special medical recommendation. The new study does not determine that fish oil is harmful to everyone who takes it, but it shows that the picture is more complex than the perception that it is a supplement that is automatically good for everyone.

One of the prominent findings in the study concerned atrial fibrillation. This is a disorder in which the heart does not beat at a regular rhythm. The disorder can appear without clear symptoms, but it is important from a medical perspective because it can increase the risk of blood clot formation and stroke. Among people who did not suffer from cardiovascular diseases at the beginning of the follow-up, those who reported regular use of fish oil were at a 13% higher risk of developing the disorder.

In addition, a link to a 5% increase in the risk of stroke was found in the same population. It is important to understand that this is a relative increase in risk. The figure does not mean that 5 out of every 100 people who take fish oil will have a stroke, but that the risk found in the user group was 5% higher relative to the group that did not use the supplement regularly.

However, when the researchers checked people who already suffered from cardiovascular diseases, a different picture emerged. For them, regular use of fish oil was linked in some cases to better results. Among people who already suffered from atrial fibrillation, the use of the supplement was linked to a 15% lower risk of progression to a heart attack. Among people with heart failure, a link to a 9% lower risk of death was found.

The gap between the two groups is one of the central points in the study. It shows that fish oil cannot be treated in the same way for a healthy person and for a person who is already dealing with heart disease. The results also do not mean that every heart patient should start taking omega-3, but that the possible effect of the supplement may be different depending on the person's health status.

Cardiologist Dr. Andrew Freeman addressed the use of over-the-counter fish oil supplements and stated:

"Over-the-counter fish oil is very rarely recommended and is not included in the guidelines of any professional medical association."

These remarks highlight the difference between taking a supplement independently and using certain preparations as part of medical treatment and in accordance with the patient's condition.

The study also does not undermine the very importance of omega-3 in the diet. There is a difference between eating foods that contain omega-3 fatty acids and taking a concentrated capsule daily. Fatty fish like salmon and sardines are natural sources of omega-3, while walnuts, chia seeds, and flax seeds contain plant-based types of omega-3. When these substances arrive as part of whole food, they are consumed alongside other nutritional components.

Alongside the results, the study has an important limitation: it does not prove that the fish oil itself caused the atrial fibrillation or the stroke. This is an observational study, meaning the researchers followed people and compared those who took the supplement to those who did not take it. It is possible that there are additional differences between the groups that influenced the results. Therefore, it can be said that a link was found between the use of the supplement and the risks, but it cannot be determined on the basis of this study alone that the capsules are what caused them.

Omega-3 has been at the center of the discussion on heart disease prevention for years. Alongside studies that pointed to possible benefits of these fatty acids in certain situations, other studies did not find a clear advantage in taking supplements among the general population. The differences between the studies are related, among other things, to the type of preparation, the dosage, the health status of the participants, and the question of whether it is omega-3 that comes from food or a concentrated supplement.

The current study adds to this discussion data from an especially large population and over a long follow-up period. The central message that emerges from it is not that fish oil is necessarily dangerous, but that it should not be seen as a supplement that automatically protects the heart of every person. For those who take it regularly, especially following a recommendation or medical treatment, the findings are not a reason to stop use independently, but emphasize the importance of tailoring dietary supplements to the personal medical condition.