%0 Journal Article %T Clinical Investigation: Determinants of Blood Cell Omega-3 Fatty Acid Content %A Robert C. Block %A William S. Harris and James V. PottalaBackgroundResults:ppppConclusions %J The Open Biomarkers Journal %D 2008 %I %R 10.2174/1875318300801010001] %X Background: Although red blood cell eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA) content (the Omega-3 Index) predicts cardiovascular death, the factors determining the Index are unknown. Methods: In 704 outpatients, we undertook an investigation of the clinical determinants of the Index. Results: Factors associated with the Index in decreasing order were: EPA+DHA supplement use, fish consumption frequency, triglyceride level, age, high cholesterol history, and smoking. These factors explained 59% of Index variability, with capsules/fish intake together accounting for 47%. The Index increased by 13% (p< 0.0001) for each serving level increase in fish intake and EPA+DHA supplementation correlated with a 58% increase (p< 0.0001) regardless of background fish intake (p=0.25; test for interaction). A 100 mg/dL decrease in serum triglycerides was associated with a 15% higher (p<0.0001) Index. Conclusions: The intake of EPA+DHA-rich foods and supplements principally determined the Omega-3 Index, but explained only about half of the variability. %U http://www.benthamscience.com/open/tobiomj/articles/V001/1TOBIOMJ.htm