How Nicotinamide May Reduce Skin Cancer Risk
Dr. Keith A. Hnilica DVM, MS, MBA, DACVD
6 min read
A new large-scale Veterans Affairs study has confirmed what smaller clinical trials hinted at years ago—nicotinamide (vitamin B3), taken at 500 mg twice daily, can significantly reduce the risk of new skin cancers, especially when started early after the first diagnosis.
Led by Dr. Lee Wheless of Vanderbilt University, the study analyzed over 33,000 patients with a history of skin cancer. Results showed a 14% overall reduction in skin cancer risk among those taking nicotinamide—and an impressive 56% reduction when supplementation began right after the first episode of skin cancer. The protective effect, however, gradually declined when nicotinamide was started later, after multiple cancers had already occurred.
The research, published in JAMA Dermatology (September 2024), supports findings from the 2015 ONTRAC trial, which first linked oral nicotinamide to reduced rates of nonmelanoma skin cancers and actinic keratoses. But this new study stands out for its sheer size and real-world design, drawing on the Veterans Health Administration's extensive patient database.
The most striking benefit was seen for cutaneous squamous cell carcinoma (cSCC), where nicotinamide users experienced about a 22% lower risk overall and up to a 50% lower risk when supplementation began early. Even organ transplant patients, a high-risk group, saw a 53% reduction in cSCC risk if they started the supplement after their first or second cancer.
Dermatologists such as Dr. Sarah Arron and Dr. Melissa Pugliano-Mauro say the evidence is now strong enough to make nicotinamide part of routine prevention for high-risk patients, noting its low cost, minimal side effects, and potential to prevent repeat skin cancers. As Dr. Arron stated, "This should change our practice."
For most adults, nicotinamide is safe, inexpensive, and available over the counter. While not everyone with sun damage needs it, those who have had even one skin cancer may gain a lasting protective benefit—a simple vitamin helping the body defend itself, cell by cell, against the world's most common cancer.
