IntroductionGlobally, breastfeeding rates continue to decline while childhood obesity rates remain high. A comprehensive understanding of the relationship between breastfeeding and obesity and the identification of gaps in the current literature is necessary to determine the next steps in research and health promotion efforts in this area.ObjectiveThe purpose of this paper was to conduct a systematic mapping of reviews in order to evaluate the current literature and determine the associations between breastfeeding and childhood obesity risk.MethodsMedline (1946 to present), PubMed (NLM), Embase (1947 to present), Cochrane, PsycINFO, and CINAHL were searched. The studies had to be review articles looking at the association between breastfeeding and obesity. Only peer-reviewed articles published in English between 1946 and May 17, 2016 with available full texts were included in the final mapping of reviews.ResultsTwenty-nine review articles were included of which nine were meta-analyses. Variation in operationalization of exposure (breastfeeding) and outcome (overweight/obesity) variables is one of the most notable findings among the various systematic reviews. Breastfeeding was classified either as ever versus never or exclusive versus not exclusive or breastfeeding versus bottle-feeding or a combination of the three. There was variability in measurement of the duration of exclusive breastfeeding, which ranged from <1 to >12 months with majority between 1 and 6 months. Overweight and obesity was also variously classified using different parameters including weight status, BMI percentile, weight for length, waist-hip circumference, skinfold thickness, and various measures of obesity (fat mass, percent fat mass, and fat-free mass).ConclusionResults support a strong inverse association between breastfeeding and risk of obesity in the child. Covariates influencing this association included birth weight, socioeconomic status, maternal smoking, parental weight status, and sibling status (in twin studies). Breastfeeding initiation, duration, and exclusivity were the three ways in which breastfeeding was operationalized, while weight status and BMI were the predominant ways in which child obesity was measured. Future research focusing on a geographically and ethnically diverse population, using experimental designs, and longer duration of follow-up in the child is warranted.