Our bodies require nicotinamide, a form of vitamin B3 (also known as niacin), in small quantities, for regular functions and maintenance of overall health. While found naturally in plant- and animal-based foods, over-the-counter supplements are also available to provide additional vitamin B3 to those who don’t obtain enough through diet.
The literature shows an inconsistency in published data describing the potential cancer prevention properties of vitamin B3. A 2015 study including 385 participants with a history of nonmelanoma skin cancer demonstrated that nicotinamide supplementation significantly reduced the risk of developing new nonmelanoma skin cancers. However, a 2023 study focused on a cohort of 158 immunosuppressed organ-transplant patients (who exhibit an increased risk of skin cancer incidence) failed to show a benefit of vitamin B3 supplements administered at the same dose and schedule as the previous study. Then, a more recent study published three months ago reported a reduction of certain nonmelanoma skin cancers in individuals who took vitamin B3 supplements for one to two years.
The conflicting reports on the potential benefits of vitamin B3 on skin cancer led to a large-scale clinical trial carried out by researchers associated with the Veterans Health Administration (VA). The authors of the study point out the unique positioning of the VA to take on these critical research questions. Central among the challenges faced when researching an over-the-counter supplement like vitamin B3 is that we cannot easily track prescriptions through insurance and Medicare claims. In addition, nonmelanoma skin cancers do not carry the same standardized reporting criteria as invasive malignancies. However, the VA tracks prescriptions of vitamin B3, so use of the supplement is well documented. Further, the comprehensive records of treatments collected by the VA allow interpretation of nonmelanoma skin cancer much more accurately than in systems used by other healthcare providers.
With the robust capabilities of the VA system, a team of researchers conducted the first large-scale study addressing the efficacy of nicotinamide supplementation for skin cancer prevention. The study, recently published in JAMA Dermatology, utilized data from the Veterans Affairs Corporate Data Warehouse (CDW).
The researchers interrogated data from 33,822 patients, finding 12,287 with nicotinamide exposure, as defined by a prescription of 500 mg twice a day for 30 days or longer. The remaining 21,479 patients, considered unexposed, served as matched controls.
The analysis found a 14% reduction in skin cancer risk in individuals prescribed vitamin B3. Further, patients diagnosed with skin cancer who began nicotinamide supplementation after diagnosis had a 54% reduced risk of developing a second skin cancer. The researchers observed a risk reduction in overall skin cancers, basal cell carcinoma (BCC), and cutaneous squamous cell carcinoma (cSCC).
Similar to the previous study in organ-transplant recipients, the current study reported no effect of nicotinamide on overall skin cancer incidence in this subset of patients. Yet, the study did report a reduction in cSCC in exposed organ-transplant recipients.
This large-scale study shows a definitive decrease in the risk of skin cancer in individuals exposed to nicotinamide. The findings support efforts to educate health care professionals and patients about the benefits of over-the-counter nicotinamide supplementation for skin cancer prevention, particularly in patients who have an initial nonmelanoma skin cancer diagnosis.
Sources: NEJM (Chen), NEJM (Allen), Arch Dermatol Res, JAMA Dermatol