Wearing sunscreen and avoiding excessive UV exposure are well-known ways to reduce the risk of skin cancer. A new study suggests some people can add another approach to the list: taking nicotinamide supplements.
Using these supplements slashed the risk of developing non-melanoma skin cancers by 54% among people who’d had the disease once before, according to the study.
That’s a “very important” finding that all dermatologists should pay attention to, said Kelly Nelson, MD, a professor of dermatology and internal medicine at the University of Texas MD Anderson Cancer Center, who was not involved in the research.
“I’m hopeful that this manuscript will really change practice” for doctors across the country, Nelson told Health.
Nicotinamide is a form of niacin, or vitamin B3, found naturally in foods such as poultry, fish, and some grains and seeds. Once absorbed by the body, it is converted into nicotinamide adenine dinucleotide (NAD), which plays a role in energy production, cellular communication, DNA repair, and more.
The new study, which was published in JAMA Dermatology, isn’t the first to suggest that nicotinamide helps prevent skin cancer. In 2015, a group of Australian researchers published a small study with the same finding.
A 2023 follow-up study conducted among organ transplant recipients, however, failed to duplicate that result. And a 2024 study also raised concerns that excess niacin may increase cardiovascular disease risk.
Lee Wheless, MD, PhD, an assistant professor of dermatology and epidemiology at Vanderbilt University Medical Center and senior author of the new JAMA Dermatology study, wanted to cut through the back-and-forth to find the truth about nicotinamide.
“My group came into all of this and said, ‘We’ve got access to some very large datasets. Let’s take a look at this,'” he said.
Using health records from Veterans Health Administration patients, Wheless and his team compared more than 12,000 people who’d taken 500-milligram nicotinamide supplements twice a day for at least a month against about 21,000 people who hadn’t.
Everyone in the study previously had at least one non-melanoma skin cancer. The researchers were interested in whether the nicotinamide users were less likely to have additional diagnoses moving forward. They specifically tracked cases of basal cell carcinoma and cutaneous squamous cell carcinoma, the two most common forms of skin cancer.
Across the entire study group, nicotinamide supplementation was linked to a 22% reduction in the rate of new cutaneous squamous cell carcinomas, but no reduction in basal cell carcinomas. That worked out to a 14% lower risk of new skin cancers overall.
The picture changed, however, when the researchers looked at people who started taking nicotinamide after their first skin cancer. Among these early adopters, nicotinamide supplementation was linked to a “huge benefit,” Wheless said: “over a 50% reduction in the risk of subsequent skin cancer,” regardless of type.
The supplement’s potential to prevent cancer seems to trace back to NAD’s ability to help with DNA repair.
“As we are being exposed to the sun, we are developing DNA damage,” Wheless explained. “Anything that is not repaired pretty rapidly will ultimately go on and become a mutation,” potentially resulting in skin cancer. Improving repair processes, then, may prevent cancers from forming.
That said, the benefits seemed to shrink with each additional diagnosis before starting nicotinamide, disappearing entirely after about seven prior cancers.
Many dermatologists, including Nelson, already recommended nicotinamide supplements to skin cancer patients at risk of having additional cases—but “we often had to couch that discussion in it being based on fairly small studies,” she said. The new study, which was large and well-designed, makes her more confident in offering that recommendation, she said.
Rajani Katta, MD, a Texas-based dermatologist who studies the role of diet in skin disease, agreed. “I am very, very cautious about supplement use,” she said. “But this one, so far, I find very promising.”
Both doctors, however, said there’s not yet enough data to say whether nicotinamide supplementation is beneficial for people who have never had skin cancer, or who have had melanoma—which is less common but deadlier than basal and squamous cell disease.
While the new study suggests nicotinamide is safe, Katta said she’d like to see more long-term safety data, as well as additional studies in more diverse populations. (The study group was overwhelmingly white and male.)
If you’re considering a nicotinamide supplement, talk to your doctor first, Katta advised. And when it comes to skin cancer prevention, “far and away, sun-protective behaviors are the most important,” she emphasized. “Your dietary choices are not going to be able to counteract a lot of UV radiation.”
