Critical Differences Between Dietary Supplement and Prescription Omega-3 Fatty Acids: A Narrative Review

Abstract

Introduction: Currently available omega-3 (OM-3) fatty acid products in the US are either nonprescription dietary supplements (e.g., fish oils) or prescription (Rx) medications. As such, we aimed to describe critical therapeutic differences among the OM-3 fatty acids, focusing on differences between fish oil supplements and Rx OM-3s. Methods: A narrative review of known papers salient to this topic was conducted. Results: Despite the multiple purported clinical benefits, the published evidence for OM-3 dietary supplements is generally insufficient, inconsistent, or negative. Rx OM-3 products are indicated as an adjunct to diet to reduce triglycerides (TG) in adults with severe hypertriglyceridemia (TG C 500 mg/dl). Recently, the Rx eicosapentaenoic acid (EPA)-only OM-3, icosapent ethyl, demonstrated cardiovascular (CV) risk reduction among statin-treated patients at high risk of CV disease in a large CV outcomes trial (CVOT), and is now also indicated as an adjunct to maximally tolerated statin therapy to reduce the risk of myocardial infarction, stroke, coronary revascularization, and unstable angina requiring hospitalization in adult patients with elevated TG (C 150 mg/ dL) and established CVD or diabetes mellitus and C 2 additional risk factors for CVD. In contrast to the rigorous regulatory standards for safety, efficacy, and manufacturing of medications (whether Rx or over the counter), the Food and Drug Administration manages dietary supplements as food. Issues specific to OM-3 dietary supplements include variable content, labeling inconsistencies, and poor product quality/impurity. Given these issues, OM-3 dietary supplements should not be substituted for Rx OM-3 products. The efficacy of the EPA-only Rx OM-3 product in a large CVOT cannot be extrapolated to other OM-3 products. Conclusion: Consumers and health care providers need to recognize critical differences between Rx and OM-3 dietary supplements to ensure appropriate use of each OM-3 product.

Cold-Pressed Nigella Sativa Oil Standardized to 3% Thymoquinone Potentiates Omega-3 Protection against Obesity-Induced Oxidative Stress, Inflammation, and Markers of Insulin Resistance Accompanied with Conversion of White to Beige Fat in Mice

“…This metabolic switch in WAT lowers triglycerides and induces mitochondrial biogenesis [ 27 ]. Fish oil mainly reduces triglycerides and inflammation, but the results have been variable [ 28 , 29 , 30 ].…”

Change in Blood and Benign Breast Biomarkers in Women Undergoing a Weight-Loss Intervention Randomized to High-Dose ω-3 Fatty Acids versus Placebo

“…The VITAL trial using one-fourth of the dose of combined EPA + DHA esters we employed did not show evidence of prevention of cancer or cardiovascular disease [49]. However, the dose in the VITAL trial likely produced only a fraction of systemic levels obtained in animal studies where cancer preventive effects were observed [17,18,23] different CVD outcomes in ω-3-FA arms for the ASCEND (0.84 g total DHA + EPA/day) vs REDUCE-IT trials (4 g EPA/day) [50].…”

Can fish oils help to prevent cardiovascular disease?

“…2,3,21 However, the historical uncertainty surrounding the actual clinical evidence base for the efficacy of omega-3 fish oils has severely curtailed their clinical role. Hence, clinical interest is likely to stay focused on adjunctively harnessing the ability of prescription omega-3 acid ethyl esters (as medicinal products distinct from dietary omega-3 fish oil supplements 15,35,36 ) to lower elevated triglycerides in the overall management of residual cardiovascular risk.…”