DHA increases the Omega-3 Index more than EPA


Omega-3 fatty acids are needed by our body not only for normal cellular functioning, but they also have beneficial effects on our health. These beneficial effects are particularly well established on cardiovascular health, and for this reason, supplementation with EPA and DHA (the main omega-3 fatty acids) is recommended by various health institutions.

The Omega-3 Index reflects the amount of omega-3 fatty acids in the major organs, including cardiac tissue; it is calculated as the proportion of EPA plus DHA in red blood cell membranes with respect to the total amount of fatty acids, and is expressed as a percentage, for example: if 6% of all the fatty acids present in red cell membranes is EPA and DHA, the Omega-3 Index is 6%. It is considered that an Omega-3 Index greater than 8% is optimal, while an index of less than 4% is insufficient. A low index may be regarded as a risk factor of health problems such as high blood pressure and high blood levels of bad cholesterol.

The Omega-3 Index is influenced by the intake of EPA and DHA from foods or from supplementation with fish oil (every 4 g of EPA and DHA ingested per month increase the Omega-3 Index by 0.24%), although other factors also affect it: age, body mass index, gender, and physical activity, among others.

Recent studies have suggested that EPA and DHA have distinct effects on health. One of them has showed that the increase in the Omega-3 Index after supplementation with DHA is significantly greater than after supplementation with EPA. Future studies will help us to understand the consequences of this finding.


Allaire J, Harris WS, Vors C et al. Supplementation with high-dose docosahexaenoic acid increases the Omega-3 Index more than high-dose eicosapentaenoic acid. Prostaglandins Leukot Essent Fatty Acids. 2017 May;120:8-14. https://www.ncbi.nlm.nih.gov/pubmed/28515020

Sands SA, Reid KJ, Windsor SL et al. The impact of age, body mass index, and fish intake on the EPA and DHA content of human erythrocytes. Lipids. 2005;40(4):343-7. https://www.ncbi.nlm.nih.gov/pubmed/16028715