Effects of breastfeeding on trajectories of body fat and BMI throughout childhood.

Objective: To investigate the effect of breastfeeding in healthy boys and girls on their trajectories of percent body fat (%BF) and BMI standard deviation scores (BMI-SDS) throughout childhood.

Methods And Procedures: Analyses of the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study included data from 219 male and 215 female term participants, born between 1984 and 1999, with repeated anthropometric measurements between 0.5 and 7 years and prospective data on duration of breastfeeding.

Results: Among boys with an overweight mother (OW-M), analyses adjusted for potential confounders revealed that not or shortly breastfed (< or =17 weeks) boys did not experience the age-dependent decrease in %BF seen in all children with normal weight mothers (NW-Ms). In contrast, boys fully breastfed for >17 weeks were protected against the adverse effect of maternal overweight (effect of long breastfeeding vs. no/short breastfeeding among boys with OW-Ms: 0.46%/year; s.e. 0.18; P = 0.01). There was also a suggestion of an interaction between maternal overweight and breastfeeding for the BMI-SDS trajectory (0.08 SDS/year; s.e. 0.04; P = 0.07). Among boys with NW-Ms mothers and the corresponding subgroups of girls, breastfeeding had little effect on the development of %BF or BMI-SDS throughout childhood.

Discussion: Our study suggests that breastfeeding could offset a potential programming effect for childhood adiposity among boys with OW-Ms, to whom advice to breast-feed should thus be specifically targeted.