Breast feeding is the best way to nurture healthy newborns of healthy mothers. A number of studies have shown that breast feeding may protect against the later development of obesity and related metabolic diseases. Using data from our own meta-analysis as well as studies by other groups, in this review we systematically examine the current state of evidence regarding this topic. Breast feeding, in general, is shown to be associated later in a child's life with decreased risk of overweight, decreased blood cholesterol and blood pressure, and a reduced risk of developing type 2 diabetes. Additionally, we review data of our Kaulsdorf Cohort Study (KCS) showing, however, that these effects might be reversed when the mother is affected by a non-communicable disease such as diabetes mellitus, which alters the composition of breast milk. In particular, exposure to breast milk from diabetic mothers during the first days of life (first week; early neonatal period) seems to increase rather than decrease risk of overweight and, consecutively, impaired glucose tolerance in childhood. Taken together, current findings show clearly that breast feeding is effective in lowering the risk of developing key features of the metabolic syndrome in later life, and should therefore be promoted. With increasing prevalence of overweight and diabetes in women, however, more research is urgently needed to clarify whether breast feeding might even have negative consequences for risk of overweight and diabetogenic disturbances when the mother suffers from a metabolic disorder. From a more general perspective, breast feeding and its long-term consequences are an important paradigm for "perinatal programming" of health and disease.