The booming dietary supplements industry in the US, valued at over $50 million, witnesses approximately 60% of adults routinely incorporating supplements into their health and wellness regimen.
Central to this market are fish oil supplements, which often tout benefits related to heart health. However, the scientific foundation of these claims was scrutinized by researchers from the University of Texas Southwestern Medical Center. Their analysis, published on August 23 on the JAMA Cardiology website, questioned the scientific backing of these assertions.
The study emphasized that the majority of fish oil supplement labels carry health claims pertaining to heart health and other physiological aspects. Nevertheless, the researchers noted a lack of trial data demonstrating the efficacy of these claims.
Furthermore, the study revealed that the levels of crucial eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) can vary across different products.
The researchers based their analysis on data sourced from existing fish oil (and non-fish omega-3 fatty acid) supplement labels from the National Institutes of Health Dietary Supplement Label Database.
The study focused on two types of health claims related to cardiovascular disease: qualified health claims (QHCs) and structure/function claims.
Qualified health claims are sanctioned by the US Food and Drug Administration (FDA) based on an evidence review. These claims pertain to a supplement’s potential to contribute to disease treatment or prevention. Conversely, structure/function claims describe the intended impact of a dietary ingredient on the structure or function of the human body, without asserting prevention, treatment, or cure of any ailment.
Out of the 2,819 unique fish oil supplements assessed, 2,082 (73.9%) featured at least one health claim. The majority of these claims were structure/function claims.
Qualified health claims were present in 399 supplements (19.2%), with 394 related to coronary heart disease, three to blood pressure, and two to both. Notably, approximately 62% of health claims revolved around heart health.
The researchers highlighted a disconcerting aspect: “Multiple randomized clinical trials have shown no cardiovascular benefit to fish oil supplements.” They also expressed concerns about the potential misinformation arising from prevalent structure/function claims.
While the study was based on voluntarily submitted labels and had certain limitations, experts weighed in on the findings. The Council for Responsible Nutrition (CRN), a dietary supplement trade group, criticized the study, stating that structure/function claims and qualified health claims serve distinct purposes.
The research landscape concerning fish oil supplements’ impact on heart health remains complex. While several studies point to potential benefits, there is also evidence that contradicts these claims. Nutrition studies, owing to various variables affecting human health, are notoriously challenging to conduct definitively.
As consumers continue to navigate the world of dietary supplements, the study underscores the importance of critical assessment and seeking reliable, evidence-based information.