Nicotinamide (vitamin B3) linked to lower skin cancer risk in veterans, study finds

A large Veterans Affairs study found that nicotinamide, a form of vitamin B3, was linked to a lower risk of several skin cancers. The research analyzed health records of more than 33,000 U.S. veterans from 1999 to 2024 and found that those who took nicotinamide had about a 14% lower risk of developing skin cancers overall, including basal cell carcinoma and squamous cell carcinoma.

The study compared 12,287 patients who took oral nicotinamide at 500 mg twice daily for more than 30 days with 21,479 patients who did not take the supplement. Researchers matched participants by age, sex, race, and skin cancer history, and accounted for exposure to other treatments, as well as organ transplant history and chronic lymphocytic leukemia.

Researchers reported that nicotinamide supplementation was associated with a roughly 14% decrease in overall skin cancer risk, driven by lower instances of basal cell carcinoma and squamous cell carcinoma. The study also looked at recurrence: among patients who started nicotinamide right after a first skin cancer diagnosis, the risk of cancer returning fell by about 54%. The benefit was smaller for people with two or more skin cancers.

For organ transplant recipients, the overall risk difference was small unless nicotinamide was started early, when it appeared to lower the risk of squamous cell carcinoma. The authors said the results suggest a decreased risk of skin cancer among patients treated with nicotinamide, with the greatest effect seen when the supplement is initiated after the first skin cancer.

In a JAMA Dermatology podcast, co-researcher Dr. Lee Wheless of Vanderbilt University Medical Center discussed the link between skin cancer recurrence and nicotinamide exposure. He cautioned that he would not necessarily recommend that someone with a first diagnosis start taking nicotinamide immediately, noting the findings have shifted his thinking. "If a patient has developed that field cancerization already, I really question — is this going to be as effective as if we had started before?" He added that clinicians should consider starting preventive measures early, especially for patients with substantial skin damage.

Experts emphasize that the study shows association, not proven causation, and that results may not generalize beyond veterans. The data come from an observational analysis of VA records; randomized trials would be needed to confirm the preventive effect, though the study provides real-world evidence that may inform future research and clinical practice. Still, the researchers say their findings support considering nicotinamide as part of a broader skin cancer prevention strategy, particularly after an initial diagnosis. The study adds to growing interest in chemoprevention for skin cancer and reaffirms that prevention remains a priority in populations at high risk.

The findings were published based on VA data spanning 1999 to 2024 and reflect real-world use of nicotinamide as a preventive measure. Medical professionals caution that patients and clinicians should discuss risks, benefits, and timing before starting any new supplement regimen. For those seeking additional information on health topics, many institutions encourage consulting healthcare providers and reviewing peer-reviewed research in context of individual health history.