Specific infant feeding practices do not consistently explain variation in anthropometry at age 1 year in urban United States, Mexico, and China cohorts
Woo, J.G.; Guerrero, M.L.; Ruiz-Palacios, G.M.; Peng, Y.-m.; Herbers, P.M.; Yao, W.; Ortega, H.; Davidson, B.S.; McMahon, R.J.; Morrow, A.L.
Journal of Nutrition 143(2): 166-174
2013
ISSN/ISBN: 1541-6100 PMID: 23236024 DOI: 10.3945/jn.112.163857Document Number: 566766
Infant feeding practices generally influence infant growth, but it is unclear how introduction of specific foods affects growth across global populations. We studied 3 urban populations in the Global Exploration of Human Milk study to determine the association between infant feeding and anthropometry at 1 y of age. Three hundred sixty-five breastfeeding mother-infant pairs (120 US, 120 China, and 125 Mexico) were recruited soon after the infant's birth. Enrollment required agreement to breastfeed ≥75% for at least 3 mo. Weekly, 24-h, food frequency data were conducted on infants for 1 y and exclusive breastfeeding (EBF) duration and timing of specific complementary food introduction were calculated. Weight and length were measured at age 1 y and anthropometry Z-scores calculated using WHO standards. Cohorts in the 3 urban populations (Shanghai, China; Cincinnati, USA; and Mexico City, Mexico) differed by median EBF duration (5, 14, and 7 wk, respectively; P < 0.001), timing of introduction of meat/eggs/legumes (4.8, 9.3, and 7.0 mo, respectively; P < 0.0001), and other feeding practices. By age 1 y, infants in Shanghai were heavier and longer than Cincinnati and Mexico City infants (P < 0.001). Adjusting for nonfeeding covariates, the only feeding variable associated with anthropometry was EBF duration, which was modestly inversely associated with weight-for-age but not length-for-age or BMI Z-scores at 1 y. Although feeding variables differed by cohort, their impact on anthropometry differences was not consistent among cohorts. Overall, across these urban, international, breast-fed cohorts, differences in specific feeding practices did not explain the significant variation in anthropometry.