Infants cared for by people other than their parents tend to gain more weight, according to a new study says.

This may be in part because they are also less likely to be breast-fed, and more likely to be introduced to solid foods early. Earlier studies have suggested that breast-feeding for up to the first 12 months of life may confer protection against obesity.

Even children who were only in part-time child care gained about 0.4 more pounds over nine months than infants cared for by their parents. Children who were cared for by relatives gained about 0.35 more pounds.