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

The dietary supplement industry is a growing market with a variety of suppliers, producers, and distributors in terms of size and quality. Because of the little amount of regulation placed on the dietary supplement industry compared to the pharmaceutical industry in the United States, there is less pressure on supplement companies ensure that their labels accurately reflect the actual product’s content. There are few studies on the quality of fish oil sold in the U.S., particularly about quantitation of ω-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The aim of this study was to compare the amount of ω-3 fatty acids found in fish oil capsules and liquids bought from local stores to their label claim. Of the 16 fish oil products tested, 6 were ± 20% outside of the label claim for EPA and 10 of 15 were ± 20% outside of the label claim for DHA. One product did not have a label claim for DHA. The large variance in the amount of omega-3s from the product label could mislead consumers to ingesting significantly more or less than expected.