The findings serve to provide evidence of plasma fatty acid composition’s link with diabetes and other cardiometabolic risks and the effects of lifestyle interventions on this composition in children.
Fatty acid metabolism is closely associated with cardiometabolic risk, already in childhood and is a reliable indicator of dietary fat and carbohydrate quality in a given diet.
“The relative proportion of oleic acid was higher in children who consumed a lot of sugar, and lower in children who consumed plenty of whole grain products,” the study said.
“Excessive intake of sugar stimulates the body's endogenous synthesis of fatty acids, which can be detected in the plasma fatty acid composition.”
The team from the University of Eastern Finland studied 512 children aged six to eight years old.
The children and their families received nutrition and exercise counselling over a period of two years.
A four-day food record was used to evaluate food consumption. Fatty acid composition in plasma was determined by gas chromatography from a fasting blood sample.
Findings revealed a high intake of vegetable oil-based margarines (60-80% fat) was linked to a lower levels of saturated and monounsaturated fatty acids and a high polyunsaturated fatty acid content in plasma fatty acid make-up.
A higher consumption of high-fibre grain products and a lower consumption of confectionary was also linked to lower levels of monounsaturated fatty acids in plasma.
Several saturated fatty acids and that of palmitoleic acid were positively linked with cardiometabolic risk score. The opposite was true for many polyunsaturated fatty acids.
“It is possible to affect plasma fatty acid composition by a two-year individualised and family-based lifestyle intervention,” said the study’s lead author, Taisa Venäläinen, from the University of Eastern Finland.
“Of note, plasma fatty composition is not only a biomarker for dietary fat quality but also reflects the consumption of high-fibre grain products and foods high in sugar, such as candy.”
It is known that high consumption of high-sugar confectionary increases activity of delta-9-desaturase, an enzyme that helps the liver form monounsaturated fatty acids from saturated ones.
While it prevents saturated fatty acids from accumulating in the liver, it also promotes the excretion of fatty acids from the liver into the blood stream.
Previous studies show a high carbohydrate intake ups delta-9-desaturase activity in adults. This effect, along with the enzyme’s role in increasing cardiovascular disease risk, has not been shown in children until now.
“Increased enzyme activity may be due to the liver producing saturated fatty acids from sugars at an increased pace, which is harmful for lipid metabolism and overall health,” the study concluded.
Source: American Journal of Clinical Nutrition
Published online ahead of print: DOI: 10.3945/ajcn.116.136580
“Effect of a 2-y dietary and physical activity intervention on plasma fatty acid composition and estimated desaturase and elongase activities in children: the Physical Activity and Nutrition in Children Study.”
Authors: Taisa Venäläinen et al.