Skin cancer is the most common type of cancer in the world. Millions of people are diagnosed with it every year.
It often comes back again and again, especially in people who have already had it once. Until now, the main advice to prevent it has been to stay out of the sun, wear sunscreen, and get regular skin checks.
But a new study suggests that taking a simple vitamin pill could help lower the risk of getting more skin cancers.
The vitamin is called nicotinamide, a form of vitamin B3. It is easy to find in stores, inexpensive, and safe for most people. Previous small studies had suggested it might help, but now a much larger study gives stronger evidence.
Researchers looked at the health records of more than 33,000 veterans in the United States. Over 12,000 of them started taking nicotinamide at a dose of 500 mg twice a day for more than a month. The other 21,000 did not take it.
The people who took nicotinamide had a 14% lower chance of getting a new skin cancer. For those who started taking it soon after their first skin cancer, the benefit was even greater—about a 54% lower risk of getting another one.
The study found that the timing of starting the vitamin mattered a lot. People who began taking it right after their first cancer saw the best results. If they waited until after they had already had several skin cancers, the vitamin didn’t help as much.
The benefit was strongest for squamous cell carcinoma, one of the two main types of non-melanoma skin cancer. This type can be more serious and more likely to cause problems if not treated early.
Nicotinamide works by helping the skin fix damage from the sun’s UV rays. It also reduces inflammation and helps the immune system find and remove abnormal cells that could become cancer. While it’s not a cure, it adds another layer of protection for people who are at risk.
Doctors still say that avoiding too much sun, wearing hats and sunscreen, and checking your skin regularly are very important. Nicotinamide is not a replacement for these steps. But because it’s easy to take, cheap, and has very few side effects, it may be a good extra step for people who have had skin cancer before.
This study used real-world data from medical records, not a special clinical trial. So while it shows a strong link, it does not prove for sure that nicotinamide caused the lower risk. Also, most of the people in the study were older white men, so it’s unclear if the same results would apply to women or people of other backgrounds.
Even with these limits, the findings support earlier research and give hope that this simple vitamin could help many people. More studies will be needed to learn how well it works over longer time periods and in more diverse groups. The study didn’t look at whether it helps people who have never had skin cancer.
Still, for anyone who has faced the fear of a first skin cancer, this research brings a new sense of control. Taking a small daily step—like a vitamin pill—might lower the risk of going through it all over again.
If you care about nutrition, please read studies about the best time to take vitamins to prevent heart disease, and vitamin D supplements strongly reduce cancer death.
For more information about nutrition, please see recent studies about plant nutrient that could help reduce high blood pressure, and these antioxidants could help reduce dementia risk.
The study is published in JAMA Dermatology.
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