General and abdominal fat outcomes in school-age children associated with infant breastfeeding patterns.

BACKGROUND: Breastfeeding may have a protective effect on the development of obesity in later life. Not much is known about the effects of infant feeding on more-specific fat measures.
OBJECTIVE: We examined associations of breastfeeding duration and exclusiveness and age at the introduction of solid foods with general and abdominal fat outcomes in children.
DESIGN: We performed a population-based, prospective cohort study in 5063 children. Information about infant feeding was obtained by using questionnaires. At the median age of 6.0 y (95% range: 5.7 y, 6.8 y), we measured childhood anthropometric measures, total fat mass and the android:gynoid fat ratio by using dual-energy X-ray absorptiometry, and preperitoneal abdominal fat by using ultrasound.
RESULTS: We observed that, in the models adjusted for child age, sex, and height only, a shorter breastfeeding duration, nonexclusive breastfeeding, and younger age at the introduction of solid foods were associated with higher childhood general and abdominal fat measures (P-trend < 0.05) but not with higher childhood body mass index. The introduction of solid foods at a younger age but not breastfeeding duration or exclusivity was associated with higher risk of overweight or obesity (OR: 2.05; 95% CI: 1.41, 2.90). After adjustment for family-based sociodemographic, maternal lifestyle, and childhood factors, the introduction of solid food between 4 and 4.9 mo of age was associated with higher risks of overweight or obesity, but the overall trend was not significant.
CONCLUSIONS: Associations of infant breastfeeding and age at the introduction of solid foods with general and abdominal fat outcomes are explained by sociodemographic and lifestyle-related factors. Whether infant dietary composition affects specific fat outcomes at older ages should be further studied.