Supplement use continues to surge
The supplements market has expanded rapidly in recent years, with millions of people regularly taking products such as Vitamin D, iron and Omega-3. Industry estimates project steady growth through 2029, while revenues linked to widespread supplement use reached hundreds of millions last year.
Despite their popularity, questions persist about whether these supplements always deliver clear health benefits for people without underlying medical conditions.
What Omega-3 fatty acids do
Omega-3 fatty acids play an important role in brain development, heart health and inflammation control. Because the body cannot produce them naturally, they must be obtained through diet.
Common food sources include oily fish such as salmon and mackerel, as well as plant-based options like flaxseeds, chia seeds and walnuts. Health authorities generally recommend eating fish twice a week, though many people turn to supplements such as fish oil or flaxseed oil to increase intake.
Findings from a large-scale study
A 2024 study conducted by researchers at Sun Yat-Sen University and published in the BMJ examined health outcomes in more than 400,000 UK Biobank participants over a 12-year period.
The research found that healthy adults with no known heart disease who regularly took fish oil supplements had a higher risk of developing atrial fibrillation, as well as a slightly increased risk of stroke and heart attack.
Specifically, the study reported a 13% increased risk of atrial fibrillation and a 5% increased risk of stroke among frequent fish oil users without pre-existing heart conditions.
Different outcomes for people with heart disease
In contrast, the same study found potential benefits for individuals who already had cardiovascular conditions. Among those patients, Omega-3 supplementation was linked to a reduced risk of progressing from atrial fibrillation to heart attack and a lower risk of death from heart failure.
This contrast highlights how the effects of supplements may vary depending on an individual’s underlying health.
Expert reactions and limitations
The British Heart Foundation emphasized that the study identified associations rather than direct cause-and-effect relationships. Experts also noted that details such as dosage, supplement type and frequency of use were not fully specified.
As a result, researchers caution against drawing broad conclusions or making abrupt changes without medical advice.
What this means for consumers
Health specialists generally agree that Omega-3 intake through a balanced diet remains a safe and effective approach for most people. Supplements may still be appropriate for certain individuals, particularly those with diagnosed heart conditions, but routine use by healthy adults may not be risk-free.
Doctors advise that anyone considering long-term supplement use should discuss it with a healthcare professional, especially if they have concerns about heart rhythm, stroke risk or existing medical conditions.