Breastfeeding, rapid growth in the first year of life and excess weight at age 2 years: The 3D Cohort Study

Objective: To assess relationships between breastfeeding, rapid growth in the first year of life, and overweight/obesity status at age 2. Design: As part of an observational, longitudinal study beginning in early pregnancy, multivariable logistic regressions were used to assess associations between breastfeeding duration (total and exclusive) and rapid weight gain (RWG) between birth and age 1, and to determine predictors of overweight/obesity status at age 2. Setting: 9 hospitals located in the province of Quebec, Canada. Participants: 1599 term infants participating in the 3D Cohort Study Results: Children having RWG in the first year and those having excess weight at age 2 accounted for 28% and <10%, respectively. In multivariable models, children breastfed <6 months and from 6 months to <1 year were, respectively, 2.5 times (OR: 2.45; 95% CI: 1.76-3.41) and 1.8 times (OR: 1.78; 1.29-2.45) more likely to show RWG up to age 1 compared to children breastfed ≥ 1 year. Children exclusively breastfed < 3 months had significantly greater odds of RWG in the first year (OR: 1.94; 1.25-3.04) compared to children exclusively breastfed for ≥6 months. Associations between breastfeeding duration (total or exclusive) and excess weight at age 2 were not detected. RWG in the first year was found to be the main predictor of excess weight at age 2 (OR: 6.98; 4.35-11.47). Conclusions: The potential beneficial effects of breastfeeding on rate of growth in the first year of life suggest that interventions promoting breastfeeding are relevant for obesity prevention early in life.