Breastfeeding and prevention of childhood obesity: a narrative review of behavioral, hormonal, and microbiome programming.

Childhood obesity has emerged as a major public health concern worldwide, with increasing prevalence in high-income countries. Growing evidence suggests that early-life nutrition, particularly breastfeeding, plays a critical role in reducing obesity that shaping long-term metabolic health. This narrative review highlight association between breastfeeding duration, exclusivity, and childhood obesity risk, synthesizing current evidence while exploring potential biological and behavioral mechanisms. Most studies report that breastfeeding, particularly when exclusive and sustained for longer durations, is associated with a reduced risk of childhood overweight and obesity. Evidence consistently shows that breastfed infants exhibit healthier growth trajectories, lower rates of rapid weight gain, and reduced adiposity compared to formula-fed infants. Several studies also identify plausible biological mechanisms, including appetite regulation, favorable insulin responses, and the influence of bioactive components in human milk, such as leptin, adiponectin, ghrelin, insulin-like growth factors (IGFs) and gut microbiome modulating factors. Nonetheless, some studies show weak or non-significant associations, often attributable to methodological differences, inconsistent breastfeeding practices, or inadequate adjustment for confounders such as maternal BMI and socioeconomic status. Current literature indicates that breastfeeding may serve as a protective factor against childhood obesity, highlighting its relevance in early-life nutrition and long-term health outcomes. This review underscores that promoting exclusive breastfeeding for at least 6 months should be a cornerstone of public health strategies to prevent childhood obesity.