Fish oil (FO) supplements are considered a source of omega-3 fatty acids commonly used to reduce cardiovascular risk. However, emerging data suggested that instead of reducing the risk, it may actually increase the risk of heart attack and stroke among individuals without any previous cardiovascular disease. A study by Chen et al., (2024) evaluated the effects of FO supplements on the clinical course of cardiovascular disease (CVD), from a healthy state to atrial fibrillation, major adverse cardiovascular events (MACEs) and subsequent death. The study included 415, 737 participants aged 40-69 years, enrolled in the UK Biobank study. Among the 415,737 participants free of CVD, 18,367 patients with incidence of AF, 22,636 with MACEs, and 22,140 deaths during follow-up period were identified. Remarkably, regular use of FO supplements showed benefit in those with established CVD, but not for those with pre-existing CVD. More worryingly, individuals with no reported CVD who regularly took FO supplements had a 13% higher risk of developing AF, and 5% higher risk of having a stroke than those who had good health and did not use FO. These findings suggested that regular use of FO supplements might have different roles in the progression of CVD. Some even advocated that when FO is considered, it is important to consume prescription-grade FO rather than counter FO to ensure the quality. Nonetheless, such reported findings particularly those suggestive of FO as doing more harm than good in normal individuals require further understanding prior to labelling FO as the public enemy!

References

Chen G, et al. BMJ Medicine 2024; 3(1): e000451.