Comparison of fatty acid compositions of omega-3 fatty acids-containing dietary supplements for pregnant women

Abstract

Long-chain omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), are important for the neurological development of the fetus during pregnancy. Since dietary intake of EPA and DHA is generally insufficient in the general population, dietary supplements are recommended for pregnant women. This study aims to analyze the fatty acid composition of commercially produced dietary supplements containing omega-3 fatty acids for pregnant women, to determine the differences between products, and to evaluate the consistency of DHA:EPA ratios with label claims. In current research, the fatty acid composition of 9 different brands of dietary supplements was determined using gas chromatography. All supplements contained both EPA and DHA, though in widely varying proportions. EPA and DHA percentages ranged from 4.8 to 19.7% and 3.3 to 59.4%, respectively. Brands 1 and 6 contained significantly lower EPA and DHA levels compared to other brands. Furthermore, three supplements (Brands 1, 4, and 6) displayed DHA:EPA ratio variances exceeding ±20% of their labeled declarations. Large variation in fatty acid composition among supplements underscores the need for rigorous quality control and accurate omega-3 labeling.

Keywords

• Dietary supplements
• Eicosapentaenoic acid
• Docosahexaenoic acid
• Fatty acid composition

Ethical Statement

The authors declare that this study does not include experiments with human or animal subjects, so ethics committee approval is not required.

Thanks

The analyses were carried out in the Research Laboratory of the Department of Nutrition and Dietetics, Nezahat Keleşoğlu Faculty of Health Sciences, Necmettin Erbakan University.

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