Dietary pattern as a predictor of change in BMI z-score among girls

Objectives: To describe child and adolescent dietary patterns and to determine associations between childhood dietary pattern and longitudinal change in body mass index (BMI) z-score among girls. Population and methods: Healthy girls (n = 101) aged 8-12 years at baseline and 11-19 years at follow-up participated in a longitudinal study of growth and development. Participants kept 7-day dietary records at two points in time. We incorporated time of day, frequency, and amount of energy consumed (defined as percentage of total energy consumed per dietary event) when characterizing dietary patterns. Results: Girls ate an average of 4-5 times per day and consumed most energy in the afternoon and in the evening/ night, rather than in the morning. After controlling for baseline BMI, the mean percentage of daily energy consumed in the evening/ night was positively associated with change in BMI z- score ( P = 0.039). Eating between 4.0 and 5.9 times per day overall and no more than 1.9 times in the evening/ night daily were negatively associated with change in BMI z- score ( P = 0.002 and 0.047, respectively), after controlling for baseline BMI z- score. Discussion: Recommendations to decrease the percentage of energy coming from the evening/ night meal and the number of dietary events to no more than six times per day and two times in the evening/ night should be evaluated in future longitudinal investigations.