The Quantitation of EPA and DHA in Fish Oil Dietary Supplements Sold in the United States

Abstract

The dietary supplement industry is expanding, but it still remains far less regulated than the pharmaceutical industry, resulting in inconsistent quality control. Limited research has been performed in the U.S., particularly regarding the quantification of omega-3 fatty acids like eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The aim of this study was to quantify the omega-3 fatty acid content in fish oil capsules and liquids purchased from major stores and a grocery chain and compare the results to their label claims. A total of 6 out of 15 were found to have EPA levels ±20% and 10 out of 15 were ±20% outside of the label claim for DHA. One product did not have a label claim for EPA and DHA, but did have a claim for total omega-3 content. These discrepancies indicate that consumers may unwittingly be consuming higher or lower quantities of omega-3 fatty acids than expected, potentially affecting their health outcomes.

Keywords

• fish oil
• EPA
• DHA
• label claim
• omega-3 fatty acid