The consensus often reported is that there is a modest but significant protective effect of breast-feeding on obesity risk. Numerous investigators have reported that "breast-feeding reduces childhood adiposity." This article provides a brief review of the existing literature on breast-feeding and obesity, highlighting a number of factors that may have led to overstatement of positive effects. These include publication bias, confounding variables, and lack of long-term effects on obesity risk. Although the literature does not support the existence of a protective effect of breast-feeding, a definitive conclusion of no protective effect of breast-feeding on obesity is premature, and more research is needed. © 2012 Lippincott Williams & Wilkins.