The critical period of infant feeding for the development of early disparities in obesity

Childhood obesity is an increasing public health problem, particularly among minority infants and young children. Disparities in overweight prevalence persist and widen with age, highlighting the need to identify factors contributing to early excess weight gain. We review the behavioral, social and macro-environmental factors contributing to the development of obesogenic early feeding practices among African-American infants and young children. We then examine the sociodemographic, household factors, feeding beliefs and infant characteristics associated with age-inappropriate feeding of liquids and solids (inappropriate feeding) among mothers and infants participating the U.S. Infant Care and Risk of Obesity Study, a cohort study of 217 low-income, first-time mothers and infants followed from 3 to 18 months of age. Maternal and infant anthropometry, infant diet, and maternal and household characteristics were collected at home visits at 3, 6, 9, 12 and 18 months of age. Mixed logistic regression was used to estimate the association between maternal and infant characteristics and inappropriate feeding. Rates of age-inappropriate feeding are high; over 75% of infants received solids or juice by 3 months of age. The odds of age-inappropriate feeding were higher among mothers who were single, depressed or believed that their infant is a "greedy" baby. Inappropriate feeding was associated with higher daily energy intake in infants (β = 109.28 calories, p = 0.01) and with increased odds of high infant weight-for-length (WFL; OR = 1.74, 95%CI: 1.01-3.01). Our findings suggest that age-inappropriate complementary feeding influences current energy intakes and infant WFL, factors that may increase long-term obesity risk by shaping infant appetite, food preferences, and metabolism. Given the intractability of pediatric obesity, understanding the role of early feeding in shaping long-term health disparities is critical for developing prevention strategies to stem obesity in early childhood.