A new analysis in JAMA Dermatology  reports that nicotinamide, a form of vitamin B3, was associated with a meaningful reduction in incident skin cancers among U.S. veterans with a prior history of the disease. The findings point to an inexpensive, orally administered chemopreventive option that could help clinicians manage an especially high‑risk population. The study drew on data from more than 12,000 veterans followed over 25 years who had previously received nicotinamide a