Breastfeeding has many established benefits for child health; in fact, previous meta-analysis of research found that breastfed infants have a 26 percent reduced risk of obesity later in life.
In a study in the October 2018 Pediatrics, "Infant Feeding and Weight Gain: Separating Breastmilk from Breastfeeding and Formula from Food," researchers found that breastfeeding was associated with lower body mass index (BMI) and a reduced risk of excessive weight gain in the first year of life.
This trend was stronger with longer and more exclusive breastfeeding, independent of maternal BMI or socioeconomic status. Researchers studied 2,553 infants of women enrolled in the Canadian Healthy Infant Longitudinal Development birth cohort between 2009 and 2012 and found that 97 percent initiated breastfeeding. The median breastfeeding duration was 11 months.
The study also shows that feeding expressed breast milk from a bottle appeared to have a weaker beneficial effect compared with direct feeding at the breast, although expressed milk was still more beneficial compared to formula.
Researchers concluded that this evidence helps recommend breastfeeding but that further research about infant feeding practices and how they influence the development and prevention of childhood obesity is needed.