JAMA Dermatol

OTC vitamin B3 supplement may prevent skin cancer

September 22, 2025

Study details: This retrospective cohort study published in analyzed electronic health records of 33,822 U.S. veterans to evaluate the chemopreventive efficacy of oral nicotinamide (500 mg twice daily for >30 days). Researchers matched 12,287 nicotinamide users with 21,479 non-users, adjusting for prior skin cancer history, demographics, and other treatments. Outcomes focused on basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC), including stratification by timing of nicotinamide initiation.

Results: Nicotinamide use was associated with a 14% overall reduction in new skin cancers. The greatest benefit—54% risk reduction—was observed when supplementation began after a first skin cancer. Protective effects were strongest for cSCC. Among solid organ transplant recipients, no significant overall benefit was seen, though early use showed promise for cSCC.

Clinical impact: These findings support nicotinamide as a low-cost, well-tolerated adjunct for secondary prevention of nonmelanoma skin cancers, particularly when initiated early. While not a substitute for sun protection or surveillance, nicotinamide may shift practice toward earlier intervention. Prospective trials are needed to confirm efficacy across broader populations.

Source:

Breglio KF, et al. (2025, September 17). JAMA Dermatol. Nicotinamide for Skin Cancer Chemoprevention. https://pubmed.ncbi.nlm.nih.gov/40960808/