Li J, et al. - Given the involvement of prolactin in regulating insulin sensitivity and glucose homeostasis, researchers analyzed the prospective relationship between circulating prolactin concentrations and type 2 diabetes risk in the Nurses’ Health Study (NHS) and Nurses’ Health Study II (NHSII), with up to 22 years of follow-up. The researchers documented 699 incident type 2 diabetes cases during 156,140 person-years of follow-up. Findings revealed a lower type 2 diabetes risk within 9-10 years of follow-up since blood draw in US women in correlation with a normally high circulating total prolactin concentration. Findings supported experimental evidence suggesting a protective role of prolactin within the biologically normal range in the pathogenesis of type 2 diabetes among healthy women.