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) epsilon 85th percentile, and obesity was defined as BMI epsilon 85th percentile plus triceps and subscapular skinfolds epsilon 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 support the hypothesis that breastfeeding has a long-term lasting effect on anthropometry in this population.