Nicotinamide, a form of vitamin B3, has been used by dermatologists since 2015 as a supplement to help prevent skin cancer, especially in patients with a previous history of the disease.
This advice was based on a clinical trial with 386 people, which found that those who took 500 milligrams of nicotinamide twice a day developed fewer new skin cancers.
However, there has been limited large-scale evidence to confirm these benefits—until now.
A new study published in JAMA Dermatology on September 17 analyzed data from the Veterans Affairs (VA) Corporate Data Warehouse, which allowed researchers to track the use of nicotinamide prescribed within the VA health system.
Unlike store-bought supplements, VA prescriptions were included in medical records, giving researchers access to comprehensive treatment histories and outcomes.
The study included 33,833 patients who had been diagnosed with either basal cell carcinoma or cutaneous squamous cell carcinoma. Among them, 12,287 received nicotinamide treatment (500 mg twice daily for more than 30 days), while 21,479 did not.
Overall, those who took nicotinamide had a 14% lower risk of developing another skin cancer. If the supplement was started after a person’s first skin cancer diagnosis, the risk dropped by 54%. However, starting nicotinamide after multiple skin cancers showed less benefit. The results were particularly strong for preventing squamous cell carcinoma.
Dr. Lee Wheless, the study’s lead author and assistant professor of Dermatology and Medicine at Vanderbilt University Medical Center, highlighted the importance of these findings. He noted that current medical guidelines don’t specify when to begin nicotinamide use for skin cancer prevention.
These results suggest it may be helpful to start treatment earlier, potentially after the first skin cancer diagnosis rather than waiting until multiple cancers have occurred. However, he also emphasized the need to better identify which patients are likely to benefit, since not all will go on to develop multiple cancers.
The study also looked at outcomes in 1,334 patients who were immunocompromised, such as those who had received organ transplants. For these patients, nicotinamide did not significantly reduce overall skin cancer risk. Still, it did appear to lower the risk of squamous cell carcinoma when started early.
This large-scale analysis provides valuable insight into how an affordable, widely available supplement might be used more strategically in skin cancer prevention, especially in high-risk patients within the general population.
The study is published in JAMA Dermatology.
Copyright © 2025 Knowridge Science Report. All rights reserved.
