Breastfeeding has been proposed for protection against obesity later in life, but the evidence is inconclusive. John Reilly and colleagues from the University of Glasgow, and the Child Health Information Team, Edinburgh, UK, tested the hypothesis that breastfeeding is associated with a reduced risk of obesity in around 32,000 Scottish children. The BMI (body-mass index) of the children was assessed between the ages of 39 and 42 months, at which time breastfeeding status during early infancy (6-8 weeks of age) was established. Two measures of obesity were used, based on the largest 2% and 5% BMI figures (98th and 95th percentile, respectively) for the general population of children at that age.
Obesity was less common among breastfed children, and the association persisted after adjustment for socioeconomic status, birthweight, and sex. The relative reduction in risk of obesity among breastfed children was 30% when obesity was defined as the 98th percentile or higher for BMI.
John Reilly comments: “Our findings suggest that breastfeeding is associated with a modest reduction in childhood obesity risk. They also suggest that the reduction in risk is present in early childhood, which is unexpected on the basis of evidence from animals. Breastfeeding is therefore potentially useful for population-based strategies aimed at obesity prevention, particularly with the other benefits that breastfeeding provides.”
Contact: Dr John Reilly, University of Glasgow Department of Human Nutrition, Royal Hospital for Sick Children, Glasgow G3 8SJ, UK; T) +44 (0)141 201 0712; F) +44 (0)141 201 9275; E) jjr2y@clinmed.gla.ac.uk
Journal
The Lancet