INS and Impaired glucose tolerance: Furthermore, in a study by Zheng et al. (2015), offspring of dams fed a high‐fat high‐sugar diet during pregnancy, lactation, and postweaning (for a period of 32 weeks), exhibited an increase in BW, impaired glucose tolerance, decreased insulin sensitivity, and increased serum leptin, all of which correlated with increased POMC and MC4R expression (Zheng et al., 2015).