• Posted January 24, 2026

Vitamin B3 Supplement Linked to Lower Skin Cancer Risk

A common over-the-counter vitamin supplement may offer protection against some skin cancers, a new, large-scale study shows.

Researchers analyzed the health records of more than 33,800 U.S. veterans diagnosed with non-melanoma skin cancer and found that those who took nicotinamide, a vitamin B3 supplement, had a significantly lower risk of developing new skin cancer growths. 

The findings were recently published in JAMA Dermatology.

Nicotinamide — a form of niacin — has been studied as a potential medication to stop cancer from developing. But data on its effectiveness was limited.

The new study looked at two types of skin cancer: basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). These non-melanoma skin cancers grow in different layers of the skin. 

Together, they are the most common form of skin cancer in the U.S. They can develop anywhere on the body, but are often found on sun-exposed areas of the face, head, neck, hands and arms.

Overall, the study showed a 14% lower rate of new skin cancers among patients who took 500 mg of nicotinamide twice a day for at least a month, compared to those who didn’t.

The benefit was most pronounced when the supplement was started early in a patient's history of skin cancer. Researchers found:

• When nicotinamide was started immediately after a patient’s first-ever skin cancer diagnosis, the rate of new skin cancers dropped by 54%.

• This protective effect declined when the nicotinamide was started after a person had already had several skin cancers.

The greatest benefit was seen for cSCC, which can be more aggressive than BCC.

The study compared 12,287 patients who took nicotamide to 21,479 who did not. Most were male veterans. Their average age: 77. Researchers controlled for factors such as age, sex, race and a history of conditions like chronic lymphocytic leukemia or solid organ transplant that are treated with immune-suppressing drugs.

The researchers also performed a separate analysis among solid organ transplant recipients, a group known to have a very high risk of skin cancer. In this group, no lowered risk was found overall, although early nicotinamide use was tied to reduced cSCC incidence in this group.

The researchers concluded that the results suggest a decreased risk of skin cancer associated with nicotinamide use, with the greatest benefit seen when the supplement is started early.

Unlike other cancer-preventative medications including topical fluorouracil, which can be painful, or acitretin, which has a risk of side effects including liver failure, nicotinamide does not require laboratory monitoring and is available over-the-counter, they noted. 

“There are no guidelines for when to start treatment with nicotinamide for skin cancer prevention in the general population," study author Dr. Lee Wheless said in a news release. He’s an assistant professor of dermatology and medicine at Vanderbilt University Medical Center and a staff physician at the VA Tennessee Valley Healthcare System in Nashville, Tennessee. 

"These results would really shift our practice from starting it once patients have developed numerous skin cancers to starting it earlier," he added. "We still need to do a better job of identifying who will actually benefit, as roughly only half of patients will develop multiple skin cancers.” 

More information

The National Cancer Institute provides comprehensive information on skin cancer prevention.

SOURCES: Vanderbilt University Medical Center, news release, Sept. 17, 2025; JAMA Dermatology, Sept. 17, 2025