Fiber intake, not dietary energy density, is associated with subsequent change in BMI z-score among sub-groups of children

OBJECTIVE: Results from short-term studies demonstrate that energy density influences energy intake, but in children and adolescents the long-term effects of energy density and obesity development are sparse. We examined the longitudinal relationship between dietary energy density, fiber intake, and body weight change over 3 years among Danish children.

METHODS: Multiple regression analyses were performed using anthropometric and dietary data of 398 boys and girls (8-10 years) who were enrolled in 1997/1998 and followed up in 2000/2001. Validated 24-hour recall interviews were conducted in order to collect dietary energy intake. Overweight was defined as 1.05 SD, equivalent to the 85th percentile, of age- and sex-specific BMI z-score reference values.

RESULTS: An inverse association between fiber intake and subsequent excess weight gain was observed among the normal weight boys. In overweight boys, there was a direct association with excess weight gain. A high energy intake was associated with a higher weight gain among overweight than among normal-weight boys. No significant association between dietary energy density and subsequent excess weight change was seen. The prevalence of overweight increased from 27.1 to 29.9%. Mean Deltaz-score was +0.1 and +0.4 for boys and girls, respectively.

CONCLUSION: Dietary energy density was not associated with 3-year weight gain in boys and girls. Only energy and fiber intakes were related to weight gain, but in different ways for subgroups of normal-weight and overweight boys.