Global survey of the omega-3 fatty acids, docosahexaenoic acid and eicosapentaenoic acid in the blood stream of healthy adults.
Level 3 - non-randomized controlled study
Systematic review of cross-sectional and observational studies reporting blood biomarker levels.
PubMed 27216485 · doi:10.1016/j.plipres.2016.05.001
What was done
A systematic review was conducted of studies published in 1980 or later reporting blood levels of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) in healthy adults. A total of 298 studies met inclusion criteria. Reported fatty acid data from plasma total lipids (33%), plasma phospholipids (32%), erythrocytes (32%), and whole blood (3.0%) were converted to relative weight percentages (wt.%) and categorized into four ranges of erythrocyte equivalents: high (>8%), moderate, low, and very low (<=4%).
What was found
High EPA+DHA levels (>8%) were identified in the Sea of Japan, Scandinavia, and regions with indigenous or non-Westernized food habits. Very low blood levels (<=4%) were observed across North America, Central and South America, Europe, the Middle East, Southeast Asia, and Africa. The abstract does not provide meta-analytic pooled point estimates or confidence intervals.
Why it matters
This review establishes a worldwide map of healthy adult omega-3 status, demonstrating that the vast majority of the global population has low blood EPA+DHA concentrations.
Limits
Data were aggregated across four distinct blood fractions requiring conversion to erythrocyte equivalents, introducing potential measurement error. Total sample size across the 298 studies, exact study demographics, and risk-of-bias assessments are not reported in the abstract.
Cited by
- supports 90% of the US population and 80% globally do not consume sufficient levels of omega-3 fatty acids.