By Suherman Candra Maholtra 
A comprehensive study involving more than 33,000 participants has provided the most robust evidence to date regarding the efficacy of nicotinamide, a form of vitamin B3, in reducing the risk of nonmelanoma skin cancers. Researchers from the Vanderbilt University Medical Center and the Department of Veterans Affairs (VA) Tennessee Valley Healthcare System have determined that the supplement offers a significant protective effect, particularly when administered shortly after a patient’s first skin cancer diagnosis. The findings, which analyzed data from one of the largest healthcare databases in the United States, suggest a potential paradigm shift in dermatological preventative care, moving toward earlier intervention for high-risk individuals.
The study, led by Dr. Lee Wheless, an assistant professor of Dermatology and Medicine at Vanderbilt, sought to address a long-standing gap in clinical evidence. While smaller trials had previously suggested the benefits of nicotinamide, the medical community lacked the large-scale, longitudinal data necessary to confirm these effects across a broad and diverse population. By utilizing the VA’s extensive electronic health records, the research team was able to track the outcomes of tens of thousands of veterans, providing a level of statistical power previously unattainable in skin cancer prevention research.
The Evolution of Nicotinamide Research: From 2015 to the Present
The clinical interest in nicotinamide as a chemopreventive agent gained significant momentum in 2015 following the publication of the ONTRAC (Oral Nicotinamide to Reduce Actinic Cancer) trial. That landmark study, conducted in Australia and published in the New England Journal of Medicine, involved 386 participants who had a history of at least two nonmelanoma skin cancers within the previous five years. The ONTRAC results were promising, showing that a 500 mg dose of nicotinamide taken twice daily reduced the incidence of new nonmelanoma skin cancers by 23% compared to a placebo group.
Despite the success of the 2015 trial, dermatologists remained cautious. The sample size of 386 was relatively small, and the study duration was limited to one year. Furthermore, the participants were primarily from a specific geographic region with high UV exposure. For nearly a decade, clinicians have debated whether these findings could be generalized to the broader population.
The primary challenge in verifying the 2015 findings lay in the nature of nicotinamide itself. Because it is an over-the-counter (OTC) supplement, most patients do not require a prescription to obtain it. Consequently, its use is rarely documented in standard private-sector medical insurance claims or electronic health records. This "data shadow" made it nearly impossible for researchers to conduct large-scale observational studies using traditional datasets.
Leveraging the VA Corporate Data Warehouse
To overcome the documentation hurdles associated with OTC supplements, Dr. Wheless and his colleagues turned to the Veterans Affairs (VA) Corporate Data Warehouse (CDW). Unlike many private healthcare systems, the VA maintains a highly structured and centralized formulary. Within the VA system, nicotinamide is frequently prescribed and tracked through official pharmacy records, even though it is available without a prescription elsewhere.
This unique data environment allowed the research team to identify a massive cohort of 33,833 veterans. The researchers focused on patients who had received a baseline treatment of 500 milligrams of nicotinamide twice daily for a period exceeding 30 days. This group was then compared against a control group of veterans who had similar medical histories but did not take the supplement. By tracking the subsequent diagnoses of basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (SCC) via the VA’s diagnostic coding system, the team was able to draw clear correlations between supplement use and cancer incidence.
Analyzing the Findings: A 14% Overall Reduction and the 54% Breakthrough
The results of the study, published recently, confirmed the protective benefits of nicotinamide while revealing new nuances regarding the timing of treatment. Among the total population studied, 12,287 veterans were identified as nicotinamide users, while 21,479 were non-users. The researchers observed a 14% overall decrease in the risk of developing new nonmelanoma skin cancers among those taking the supplement.
However, the most striking data emerged when the researchers stratified the patients based on their clinical history. For patients who began taking nicotinamide immediately after being diagnosed with their first-ever skin cancer, the risk of developing a subsequent cancer plummeted by 54%. This suggests that there is a critical "window of opportunity" for intervention.
Interestingly, the study found that the protective benefits of the supplement appeared to diminish as the patient’s history of skin cancer became more extensive. For veterans who had already developed multiple skin cancers before starting the regimen, the risk reduction was less pronounced than for those who started earlier. This finding challenges the current clinical practice of many dermatologists who typically only recommend nicotinamide to "frequent flyers"—patients who are already plagued by numerous annual skin cancer recurrences.
Understanding the Biological Mechanism of Vitamin B3
To appreciate the significance of these findings, it is necessary to understand how nicotinamide functions at a cellular level. Nicotinamide is a precursor to nicotinamide adenine dinucleotide (NAD+), a coenzyme essential for cellular energy metabolism and DNA repair.
When skin cells are exposed to ultraviolet (UV) radiation from the sun, two primary forms of damage occur. First, the UV radiation directly damages the DNA, causing mutations that can lead to uncontrolled cell growth. Second, UV radiation depletes cellular energy (ATP), which is required for the enzymes responsible for DNA repair to function correctly. By supplementing with nicotinamide, patients provide their cells with the necessary building blocks to replenish ATP levels and enhance the efficiency of DNA repair mechanisms.
Furthermore, nicotinamide has been shown to reduce the immunosuppressive effects of UV radiation on the skin. UV exposure typically dampens the local immune response, allowing mutated cells to evade detection. Nicotinamide helps maintain the skin’s immune vigilance, potentially identifying and destroying precancerous cells before they evolve into clinical malignancies.
Squamous Cell Carcinoma vs. Basal Cell Carcinoma
The study also highlighted a variance in efficacy between the two most common types of nonmelanoma skin cancer. While the supplement showed benefits for both, the effect was significantly stronger for cutaneous squamous cell carcinoma (SCC) than for basal cell carcinoma (BCC).
SCC is generally considered more aggressive than BCC. While BCC rarely spreads to other parts of the body, SCC has a higher potential for metastasis and can be more disfiguring if not caught early. The fact that nicotinamide is particularly effective against SCC is of high clinical importance, as it targets the more dangerous of the two common nonmelanoma types. This differentiation helps clinicians better tailor their preventative strategies based on a patient’s specific pathology history.
Challenges in Immunocompromised Populations
A secondary focus of the study involved 1,334 patients who were immunocompromised, primarily due to solid organ transplants. Transplant recipients are at a vastly increased risk for skin cancer—often 65 to 250 times the risk of the general population—because the medications required to prevent organ rejection also suppress the body’s ability to fight off skin cancer cells.
In this specific subgroup, the overall risk reduction provided by nicotinamide did not reach statistical significance. However, the researchers did note that early use of the supplement was linked to fewer cases of squamous cell carcinoma even within this high-risk group. The lack of overall significance may be due to the smaller sample size of the transplant cohort or the overwhelming nature of the immunosuppression, which may require more intensive interventions than vitamin supplementation alone.
Shifting the Clinical Paradigm: The Call for Early Intervention
The implications of this research are expected to influence dermatological guidelines globally. Dr. Lee Wheless emphasized that the data supports a move toward earlier intervention. "These results would really shift our practice from starting it once patients have developed numerous skin cancers to starting it earlier," Wheless stated.
Currently, there are no universal guidelines regarding the exact moment a patient should begin a nicotinamide regimen. Many practitioners wait until a patient presents with a "high burden" of disease. The Vanderbilt-VA study suggests that this "wait and see" approach may result in missed opportunities to prevent a significant portion of the disease’s progression.
However, Dr. Wheless also urged a balanced approach. While the 54% reduction is substantial, roughly half of the patients who get one skin cancer will never develop a second one. Therefore, the challenge for the medical community remains identifying which patients are most likely to benefit from long-term supplementation. "We still need to do a better job of identifying who will actually benefit," Wheless noted, highlighting the need for future research into biomarkers or genetic predispositions that could predict recurrence.
Public Health and Economic Implications
Beyond the clinical benefits, the widespread adoption of nicotinamide for skin cancer prevention carries significant public health and economic implications. Nonmelanoma skin cancer is the most common form of cancer in the United States, with millions of cases diagnosed annually. The cost of treating these cancers—including surgical excisions, Mohs surgery, and follow-up care—runs into the billions of dollars every year.
Nicotinamide is a low-cost, readily available, and generally safe supplement. Unlike other chemopreventive agents, it does not carry the risk of significant side effects like gastrointestinal distress or increased liver enzymes when taken at the recommended 500 mg twice-daily dose. By reducing the incidence of new cases by even 14% on a national scale, the healthcare system could see a substantial reduction in the surgical burden and associated costs.
Conclusion and Future Directions
The study conducted by the Vanderbilt and VA teams represents a milestone in dermatological epidemiology. By harnessing the power of the VA Corporate Data Warehouse, researchers have provided the clarity that the 2015 ONTRAC trial invited but could not fully provide due to its scale.
The work was supported by a Department of Veterans Affairs grant (IK2CX002452), highlighting the role of federal funding in advancing preventative medicine. The collaboration included a multidisciplinary team from Vanderbilt, including Katyln Knox, Rachel Weiss, Siwei Zhang, PhD, Lydia Yao, MS, Yaomin Xu, PhD, and Kyle Maas, all of whom contributed to the complex data analysis required to navigate the VA’s massive records.
As the medical community digests these findings, the focus will likely turn to updating patient education materials and refining clinical pathways. For now, the message for patients with a history of skin cancer is clear: a conversation with a dermatologist about starting Vitamin B3 supplementation early may be one of the most effective steps they can take to protect their future skin health. Further research will continue to explore the optimal duration of treatment and whether these benefits extend to other populations, but the foundation for earlier, supplement-based prevention is now more solid than ever.