Objective: Snacking has been related to increased prevalence of overweight among school-age children in cross-sectional studies. It is uncertain, however, whether snacking influences the development of adiposity over time. Design: We examined whether adherence to a snacking dietary pattern was associated with greater increases in children's BMI, subscapular:triceps skinfold thickness ratio and waist circumference over a median 2?5-year follow-up. Dietary patterns were identified through principal component analysis of an FFQ administered at recruitment in 2006. Anthropometric follow-up was conducted annually. Linear mixed-effects models were used to estimate rates of change in each indicator according to quartiles of adherence to the snacking pattern. We also examined change in BMI, subscapular:triceps skinfold thickness ratio and waist circumference in relation to intake of the food items in the snacking pattern. Subjects: Children (n 961) 5-12 years of age. Setting: Public schools in Bogotá, Colombia. Results: After adjustment for age, sex, total energy intake and socio-economic status, children in the highest quartile of adherence to the snacking pattern had a 0?09 kg/m 2 per year higher BMI gain than children in the lowest quartile (P trend 5 0?05). A similar association was observed for mean change in subscapular:triceps skinfold thickness ratio (highest v. lowest quartile difference 5 0?012/year; P 5 0?03). Of the food items in the snacking pattern, soda intake was positively and significantly associated with change in BMI (P trend 5 0?01) and waist circumference (P trend 5 0?04) in multivariable analysis. Conclusions: Our results indicate that snacking and soda intake are associated with development of adiposity in school-age children.