Proportions of long-chain ω-3 fatty acids in erythrocyte membranes of Canadian adults: Results from the Canadian Health Measures Survey 2012-2015.
Level 4 - case-series / case-control
Cross-sectional population survey (Canadian Health Measures Survey)
PubMed 33675340 · doi:10.1093/ajcn/nqaa401
What was done
Researchers pooled data from 4,025 adult participants in cycles 3 and 4 (2012–2015) of the cross-sectional Canadian Health Measures Survey. They measured erythrocyte membrane proportions of omega-3 fatty acids, total omega-6 fatty acids, the Omega-3 Index (OI), and the EPA/arachidonic acid (AA) ratio, examining associations with sociodemographic, health, and lifestyle characteristics using covariate-adjusted models.
What was found
The mean Omega-3 Index was 4.5%, and nearly 40% of Canadian adults had an undesirable OI (<4%). OI was most strongly associated with omega-3 supplement use, fish intake, and race. The prevalence of an undesirable OI was significantly higher in those consuming fish less than twice weekly compared to more frequently (43.8% vs. 12.7%), in smokers compared to nonsmokers (62.7% vs. 33.4%), in whites compared to Asians (42.7% vs. 23.0%), and in adults aged 20–39 years compared to those aged 60–79 years (49.6% vs. 24.4%; all P ≤ 0.05). Supplement use and fish intake were also the strongest determinants of the EPA/AA ratio.
Why it matters
This study provides representative population-level baseline data on red blood cell fatty acid profiles in Canada, demonstrating that a substantial proportion of adults fall into a biomarker category associated with higher coronary artery disease risk.
Limits
The cross-sectional design cannot determine causal relationships. Actual clinical cardiovascular disease outcomes were not assessed, only surrogate biomarker levels. Dietary and supplement data relied on self-report, and results may not generalize outside the Canadian population.
Cited by
- supports Smokers have a lower Omega-3 Index than non-smokers.