Introduction: Enhanced dietary intake of omega-3 fatty acids may benefit persons with increased cardiovascular risk, among them obese subjects. Incorporation of omega-3 fatty acids into the plasma lipids is a prerequisite to achieve the favorable effects; however, only very few data are available on the dose of omega-3 fatty acid supplementation in children. The aim of our study was to examine the effects of the consumption of a diet supplemented with 1000 mg alpha-linolenic acid daily on plasma lipids in obese children.
Methods: In this two times six-week-long, placebo-controlled, crossover study, 9 obese children (age: 13.1 [2.5] years, body mass index: 31.2 [6.2] kg/m 2 ), median [IQR]) incorporated into their diet one egg and one meatball (50 g) per day from hens fed diets containing flaxseed oil, i.e. supplementary dietary intake of 1000 mg alpha-linolenic acid per day was provided. The fatty acid composition of plasma lipids was determined by high-resolution gas-liquid chromatography.
Results: Tendencies of increase were observed in the alpha-linolenic acid content of plasma lipids in the phospholipid, triacyl-glycerine and sterol-ester fractions after the supplementation with alpha-linolenic acid. In the non-esterified fatty acid fraction, the values of alpha-linolenic acid were significantly higher after the supplementation (0.11 [0.08] versus 0.14 [0.20], % weight/weight, p < 0.05), indicating the beginning of the accumulation of alpha-linolenic acid in plasma lipids.
Conclusion: In obese children a six-week-long supplementation of the diet with 1000 mg alpha-linolenic acid per day increased significantly the contribution of omega-3 fatty acids only to the non-esterified fatty acids of plasma lipids, but had no significant effect on the esterified fractions. Increase of the dose of supplementation may be needed to influence omega-3 fatty acid status in obese children.