Macronutrient energy intake and adiposity in non obese prepubertal children aged 5-11y (the Fleurbaix Laventie Ville Sante Study)

OBJECTIVE: To investigate associations between adiposity indices and food intake in nonobese prepubertal free-living children. SUBJECTS: Five-hundred and one children, 280 boys and 221 girls aged 5-11 y in two little towns in northern France. DESIGN: Cross-sectional survey. MAIN OUTCOME MEASURES: Height and weight, four skinfolds (biceps, triceps, subscapular, suprailiac), waist and hip girths, were measured. Sum of skinfolds (SSF), body mass index (BMI), and relative weight (RW) were calculated. Energy intake (El), percentage of energy intake ascribed to carbohydrates (%EIC), complex carbohydrates (%EICC), fats (%EIF), saturated fats (%EISF) and proteins (%EIP) were assessed by a single 24 h record. Basal metabolic rate (BMR) was estimated according to Schofield's equations. Obese (RW greater than or equal to 120%), and underreporting children according to Goldberg's and Black's equations were excluded. RESULTS: In multiple linear regressions analyses performed with hierarchical mixed models, adiposity indices were significantly and inversely associated in girls with %EIC (all P-values <0.02), and positively with %EIF (all P-values <0.05. waist girth and BMI excepted). Similar but non-significant trends were observed in boys. The relationships were not linear, and thresholds close to current dietary recommendations were highlighted. When %EIF was low, a lower percentage of energy intake ascribed to %EISF was associated with thinness. These associations remained after the exclusion of children who had an EI/BMR less than or equal to1.50. CONCLUSIONS: In nonobese prepubertal children aged 5-11 y, a high %EIC, close to dietary recommendations (greater than or equal to 55%), was associated with thinness. A high %EIF, over the upper dietary recommendation (less than or equal to 35%), was associated with a greater adiposity thickness. There was no further increase in adiposity beyond this threshold. Reasons for the absence of a linear relationship pattern between adiposity and macronutrient intake remain to be determined.