Abstract
An adequate intake of polyunsaturated fatty acids (PUFAs) plays a vital role in human health. Therefore, it is important to assess PUFA intakes in different populations and validate them with biomarkers, but only a few small studies are in paediatric populations. We calculated the dietary intake of PUFAs and their main food sources in children and assessed associations between reported PUFA intakes and plasma proportions. Dietary intakes of 7-year-old children (n=8,242) enrolled in the Avon Longitudinal Study of Parents and Children were calculated from parental-completed food frequency questionnaire. Plasma PUFAs were measured in 5,571 children 8 months later and 4,380 children had complete dietary and plasma data. The association between dietary and plasma PUFAs proportions were estimated using Spearman’s correlation coefficients, quintile cross-classification and Cohen’s kappa coefficients. Mean total PUFA intake was 13.2g/day (sd4.2), contributing 6.5% of total energy intake; n-6 PUFA contributed 5.2% and n-3 PUFA 0.7%. The n-6:n-3 ratio was 7.9:1. Mean intakes of eicosapentaenoic acid and docosahexaenoic acid (DHA) were 35.7mg/day and 49.7mg/day, respectively. Most n-3 and n-6 PUFA intakes were weakly correlated with their respective plasma lipids (0.07≤ r ≤0.16, p<0.001). The correlation between dietary and plasma DHA was stronger though (r=0.34, p<0.001), supported by a modest level of agreement between quintiles (k=0.32). The results indicate that the FFQ was able to reasonably rank the long-chain PUFA, DHA, in this paediatric population. Public health initiatives need to address the suboptimal ratio of n-6:n-3 PUFAs and very low n-3 long-chain PUFA intakes in school-aged children in the UK.
Genetic variations in the FADS1, FADS2 genes influence the proportions of long-chain n-6 polyunsaturated fatty acids in erythrocyte and plasma lipids