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) > or = 85(th) percentile, and obesity was defined as BMI > or = 85(th) percentile plus triceps and subscapular skinfolds > or = 90(th) 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.