Objectives: To evaluate the intake, plasma concentrations and postprandial response of trans fatty acids in obese and control children at prepubertal age in order to detect potential associations with childhood obesity.
Design: Case-control study, clinical dietary intervention with a 428 kcal standardized breakfast and longitudinal 3 h postprandial follow-up for trans fatty acid plasma levels.
Subjects: Fifty-four children aged 6-13 years of both sexes, 34 obese (body mass index >97th percentile for age and sex) and 20 non-obese (control group) at prepubertal period (Tanner I).
Measurements: Various anthropometric parameters and sex hormones, fasting insulin and glucose, estimation of dietary trans fatty acid intake and their plasma quantitation in fasting conditions, and for 3 h following intake of a standardized breakfast.
Results: Dietary trans fatty acid intake was less than 0.4% of total energy in both groups, with a trend towards higher intake in obese children. Fasting plasma trans fatty acid concentrations and percentages were similar in both groups. However, trans fatty acid levels at +3 h were significantly higher than at 0 h in obese children, but not in controls (obese, 0 h: 2.38+/-0.29; 3 h: 3.62+/-0.45; controls, 0 h: 2.29+/-0.24; 3.14+/-0.49 mg/dl); cis monounsaturated fatty acid concentrations were not significantly affected by the postprandial interval. Obese children exhibited hyperinsulinemia and insulin resistance; however, trans fatty acid intake or their plasma levels were not associated with them.
Conclusion: There is a low intake of trans fatty acids in Southern Spanish children, which is supported by their low concentrations in plasma. No difference in trans fatty acid intake is observed between obese and control children, although plasma levels remain higher in obese than in control children after 3 h of a meal. A marked insulin resistance is seen in obese, but it is not correlated with either trans fatty acid intake or plasma concentration.