Cross-Sectional Associations of Food Consumption with Plasma Fatty Acid Composition and Estimated Desaturase Activities in Finnish Children

Plasma fatty acid (FA) composition is known to be an indicator of dietary fat quality, but the associations of other dietary factors with plasma FA composition remain unknown in children. We investigated the cross sectional associations of food consumption with the proportions of FA and estimated desaturase activities in plasma cholesteryl esters (CE) and phospholipids (PL) among children. The subjects were a population sample of 423 children aged 6 to 8 years examined at baseline of The Physical Activity and Nutrition in Children (PANIC) Study. We assessed food consumption by food records and plasma FA composition by gas chromatography. We used linear regression models adjusted for age, sex, physical activity and total energy intake to analyze the associations. A higher consumption of vegetable oil based margarine (fat 60 to 80 per cent) was associated with a higher proportion of linoleic and alpha linolenic acids in plasma CE and PL. A higher consumption of high-fiber grain products was related to a lower proportion of oleic acid in CE and PL. The consumption of candy was directly associated with the proportion of palmitoleic and oleic acid in plasma CE. The consumption of vegetable oil based margarine was inversely associated with estimated stearoyl CoA desaturase activity in plasma CE and PL and the consumption of candy was directly related to it in plasma CE. The results of our study suggest that plasma  FA composition is not only a biomarker for dietary fat quality but also reflects the consumption of high fiber grain products and foods high in sugar among children. (Authors abstract)

Plasma fatty acid (FA) composition has been found to be influenced by several factors including diet, physical activity, overweight, genetic factors, age, sex and endogenous metabolism of FA . Also metabolic syndrome, type 2 diabetes and cardiovascular diseases have been observed to affect the FA composition in plasma and adipose tissue. Plasma FA composition may also predict the risk of developing metabolic syndrome, type 2 diabetes and cardiovascular diseases in adults.  Plasma FA composition is a reliable indicator of the quality of dietary fat in adults and children. The FA composition of plasma cholesteryl esters (CE) and phospholipids (PL) reflects the dietary fat intake of the last weeks or months. This study investigated the cross sectional associations of the consumption of variety of food items with FA composition and estimated desaturase activities in plasma CE and PL in a population sample of children 6 to 8 years of age. The study hypothesized that the consumption of foods, that are main sources of dietary SFA, MUFA and PUFA, but also fiber and sugar, are related to plasma FA composition and estimated desaturase activities in plasma CE and PL.

The results of this study in a population sample of 423 children show that a higher consumption of vegetable oil based margarine (fat 60 to 80 per cent) is related to higher plasma proportions of PUFA such as linoleic acid and alpha linolenic acid, low in SFA such as myristic acid, palmitic acid and stearic acid and low in MUFA such as oleic acid. These findings are in line with the results of earlier studies among children and adults. A higher consumption of high fiber grain products was associated with a lower proportion of oleic acid in plasma CE and PL and that a higher consumption of candy is related to higher proportion of palmitoleic acid and oleic acid in plasma CE among children.  As expected, a higher consumption of vegetable oil based margarine (fat 60 to 80 per cent) was related to higher proportions of linoleic and a linolenic acid in plasma CE and PL. A higher consumption of vegetable oil based margarine (fat 60 to 80 per cent ) was also related to a lower proportion of palmitic, stearic, palmitoleic and oleic acid in plasma CE and to a lower proportion of palmitoleic acid in plasma PL.  These observations suggest that children who consume more vegetable oil based margarine (fat 60 to 80 per cent ) have a lower dietary intake of SAFA and MUFA than other children. The results of the present study in a population sample of primary school children suggest that plasma FA composition is not only a biomarker for dietary fat quality but also reflects the consumption of high fiber grain products and foods high in sugar, such as candy. Dietary intervention studies are needed to clarify the effect of changes in the quality of dietary carbohydrates on plasma FA composition. (Editors comments)