Abstract :
Objective: To examine relationships between fish consumption and plasma selenium (Se) and red
blood-cell fatty acid (RBC FA) profile in aged subjects. We hypothesised that the importance of Se has been
underestimated when interpreting the beneficial effect of fish consumption on health. Design: Cross-sectional
analysis of data from a prospective cohort study. Setting: The EVA study in Nantes, France (1991-2002).
Subjects: 200 subjects aged 69 y with information on RBC FAs, plasma Se and completed food frequency
questionnaires. Methods: We examined correlations between the most abundant FAs, Se and number of fish
meals per week. Linear regression models were used. Results: Plasma Se was negatively correlated with RBC 6
poly-unsaturated FA (PUFAs) and positively with 3 PUFAs. Plasma Se, RBC 3 PUFAs, docosahexaenoic
acid (DHA) and eicosapentaenoic acid (EPA) increased with fish consumption. Conversely, levels of 6 PUFAs
were lower in the highest fish consumption group. All associations between plasma Se and fish consumption
remained significant when adjusting for 6 PUFAs alone or additionally for age, sex, education, diabetes,
hypertension, dyslipidemia, cardiovascular diseases, and broad food categories (meat, eggs, dairy products,
cereals, fruit and vegetable). Associations between 3 PUFAs and fish also remained significant in the same
model independently of Se. In linear regression models adjusted for demographic indicators, fish consumption
explained only 2.6% of the variance in RBC 3 FAs (6.2% for 6) but as much as 15% of the variance in
plasma selenium. Conclusions: The observed health benefits of fish consumption in the elderly could be related
not only to the increase in 3 FA intake but also to other nutrients such as selenium. It is important to consider
this observation when interpreting associations between fish consumption and health status in the elderly,
particularly with regard to brain function.
