Women with gestational diabetes mellitus are more likely to develop type 2 diabetes mellitus (T2DM) in the postpartum period. However, breastfeeding is known to reduce the risk of T2DM. In a new study in 304 women who had gestational diabetes mellitus, women who tested negative for islet autoantibodies and continued breastfeeding for >3 months had lower T2DM risk than those who did not breastfeed or who breastfed for ≤3 months. Additionally, women who breastfed had a median time to T2DM diagnosis of 12.3 years versus 2.3 years in those who did not breastfeed.