Does Breastfeeding Protect Against Childhood Obesity?
The article “Does Breastfeeding Protect Against Childhood Obesity? Moving Beyond Observational Evidence“ reviews findings from observational studies that evaluated the relationship between breastfeeding and the propensity for obesity later in childhood or adult life and was published in Current Obesity Reports. Previous systematic reviews and meta-analyses from 81 individual studies suggests that breastfeeding reduces the risk of obesity, but significant confounding and bias have prevented answering the question of whether breastfeeding is directly associated with reduced adiposity. Three specific pathways that relate human milk and infant physiology, including maternal obesity, microbiome development in the infant, and the development of taste preference and diet quality, may help us understand how infant feeding practices may be related to infant growth and development. Maternal obesity may program the offspring because of differences in hormones, metabolites, and epigenetic changes. After birth, biological differences in breastfeeding behavior and milk composition have been described. The second pathway, involving differences in the gut microbiome,are known to begin perinatally with diet during the first year of life, contributing to gut microbiome development. Observational studies have not accounted for differences in milk quality or impact on the gut microbiome. The third potential mechanism discussed in this review is that changes in taste preference and diet may be influenced by breastmilk, which is known to differ in flavor profile. However, it should be noted that it remains unknown if establishing a healthy diet protects against obesity later in life. Lastly, other factors including race/ethnicity, socioeconomic status and behavioral aspects of breastfeeding, including infant feeding cues and maternal food restrictions, may play a role in establishing feeding behaviors but it is not known if changes in these behaviors are sufficient enough to impact the risk for obesity. The authors concluded that, “By leveraging experimental, epidemiologic, and molecular methods, we can move beyond observational evidence to identify specific biologic pathways and refine the role of human milk in obesity prevention.”