Breastfeeding, body mass index, asthma and atopy in children.

The objective of this study was to determine the relationship between breastfeeding, asthma and atopy, and any influence of child body mass index (BMI). Prospective birth cohort data were used to model the association between breastfeeding duration, BMI, asthma and atopy in children at six years. After adjustment for BMI and associated covariates, breastfeeding (per additional month of feeding) was marginally associated with decreased BMI (p=0.083). BMI was significantly associated with current asthma (p=<0.0005) and atopy (p=0.055). Exclusive breastfeeding for less than four months was a risk for current asthma (p=0.033) and atopy (p=0.005). The early introduction of formula leads to an increase in child BMI and early asthma and atopy. Increased BMI is a risk factor for childhood asthma and atopy. These findings suggest that public health interventions to optimise breastfeeding duration and reduce overweight in children may help attenuate the community burden of wheezing illness early in life.