Title: Nicotinamide: A Simple Vitamin That Could Cut Skin Cancer Risk in Half

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 (Sept 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 massive 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 50% less risk when starting early. Even organ transplant patients, a high-risk group, saw a 53% reduction in cSCC risk if they began the supplement after their first or second cancer.

Dermatologists like 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. “This should change our practice,” Dr. Arron said.

For most adults, nicotinamide is safe, inexpensive, and available over-the-counter.

While not everyone with sun damage needs it, those who’ve had even one skin cancer may gain a lasting protective benefit — a simple vitamin helping the body defend itself, cell by cell, from the most common cancer in the world.