The Omega-3 Index in Athletes

Introduction: The omega-3 index (O3i), the amount of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) as a percentage of total fatty acids within erythrocytes, has emerged as a potentially important biomarker for sport. The purpose of this review is to quantify the O3i in athletes across various sporting contexts. Methods: Two databases (PubMed, Google Scholar) were searched for cross-sectional studies reporting the O3i in athletes. Simple pooled mean analyses were used to quantify the O3i in all studies and by subgroup (i.e., sex and sport). Results: Based on 18 studies (25 observations) comprised of 1,452 athletes, the combined O3i was 4.43 ± 0.59% and ranged between 2.98% and 5.19%. According to studies that reported the O3i proportion within their sample, less than 1% of all athletes had an O3i > 8%, whereas 32% of athletes had an O3i < 4%. The O3i mean difference between all subgroups (sex and sport activity) was within ± 1%. Conclusions: Athlete programs should make a concerted effort to: 1) routinely test the O3i, 2) provide education from nutrition professionals on the potential benefits and sources of n-3 fatty acids and, 3) provide meal options comprised of rich sources of EPA and DHA at least three times per week and consider providing supplementation as needed, if allowed by governing organizations.