Infant feeding and obesity at 11 years: Prospective birth cohort study

Objective. To evaluate the association between breastfeeding duration, introduction of solid or semi-solid foods before four months of age and overweight/obesity at 11 years. Methods. Prospective population-based birth cohort study, including 1 204 adolescents aged 11 years who were born in Pelotas (Brazil), in 1993, and were previously interviewed at birth, six and 12 months of age. Five explanatory variables were used: duration of any breastfeeding, duration of exclusive or predominant breastfeeding, ever breastfeeding, introduction of solid or semi-solid foods before four months of age, and feeding pattern at four months of age. Risk of overweight was defined as body mass index (BMI) ≥85th percentile, and obesity was defined as BMI ≥85th percentile plus triceps and subscapular skinfolds ≥90th percentile, using the National Center for Health Statistics curves. Results. The prevalence of risk of overweight and obesity at 11 years were 23.2% and 11.6%, respectively. The lowest prevalence of both outcomes was found among subjects who were breastfed for one to three months. However, tests for linear trend or heterogeneity did not result in a significant association between breastfeeding indicators and anthropometry at 11 years. Adjustment for sex, skin color, birth weight, maternal schooling, smoking during pregnancy and maternal pre-pregnancy BMI did not alter the findings. Conclusions. Our results do not supportthe hypothesis that breastfeeding has a long-term lasting effect on anthropometry in this population.