The vitamin B3 derivative with longevity buzz, chemoprevention data, and a complicated cancer risk conversation
Nicotinamide 500 mg BID remains evidence-supported for selected patients with recurrent BCC/cSCC risk, with benefit likely requiring ongoing therapy.
In active cancer care, NAD+ boosters deserve medication-reconciliation status, especially during chemo/radiation that depends on DNA damage or oxidative stress.
Ask specifically about “NMN,” “NAD+,” nicotinamide riboside, and anti-aging/energy supplements; patients may not volunteer them as cancer-relevant.
A low-cost form of vitamin B3 has drawn sustained interest among physicians because of its potential role in secondary prevention of nonmelanoma skin cancer among patients with prior keratinocyte carcinomas.[]
But nicotinamide (also known as niacinamide) now sits within a broader oncology discussion. As a vitamin B3 derivative and precursor in nicotinamide adenine dinucleotide (NAD+) metabolism, it intersects with pathways involved in DNA repair, cellular bioenergetics, oxidative stress response, and treatment resistance. []
That biology creates an important tension. In selected high-risk dermatology patients, nicotinamide may help reduce new basal cell and cutaneous squamous cell carcinomas. In patients with active cancer, however, NAD+-boosting supplements may carry different risks, especially if they are taken during chemotherapy or radiation therapy.
The key distinction is why the patient is taking it: nicotinamide for evidence-based skin cancer prevention is a different scenario than taking an NAD+ booster for anti-aging, energy, or general wellness during active cancer treatment.
What the research shows
The strongest clinical signal for nicotinamide remains in skin cancer prevention. In the Oral Nicotinamide to Reduce Actinic Cancer (ONTRAC) phase 3 randomized trial, 386 adults with at least two prior nonmelanoma skin cancers in the previous 5 years were assigned to 500 mg of oral nicotinamide twice daily or placebo for 12 months. []
The trial found a 23% lower rate of new nonmelanoma skin cancers during the treatment period, including basal cell carcinoma and squamous cell carcinoma, in the nicotinamide group. The protective effect did not persist after discontinuation, suggesting that ongoing therapy may be required to maintain benefit. []
More recently, a large retrospective cohort study in JAMA Dermatology analyzed Veterans Affairs EHR data from 33,822 patients. Exposure was defined as nicotinamide 500 mg twice daily for more than 30 days. [] In the matched cohort, nicotinamide use was associated with a lower rate of subsequent skin cancer, with the greatest apparent benefit when it was started after a first skin cancer diagnosis. []
The authors reported associations across basal cell carcinoma and cutaneous squamous cell carcinoma (cSCC), with the strongest signal for the latter. []
“There are no guidelines for when to start treatment with nicotinamide for skin cancer prevention in the general population. These results would really shift our practice from starting it once patients have developed numerous skin cancers to starting it earlier. We still need to do a better job of identifying who will actually benefit, as roughly only half of patients will develop multiple skin cancers,” said the JAMA Dermatology study’s corresponding author, Lee Wheless, MD, PhD, in a press release. []
Beyond chemoprevention
A 2020 review in Biomolecules summarized evidence that nicotinamide may have roles beyond skin cancer chemoprevention, including in radiotherapy-sensitizing strategies. []
The review noted phase 3 evidence for nicotinamide as an adjunct to radiotherapy in head and neck, laryngeal, and urinary bladder cancers, but also emphasized that evidence for many other cancers remains mostly preclinical. []
Much of that treatment-adjunct literature involves nicotinamide not as an OTC supplement, but as part of hypoxia-modifying regimens—often with carbogen breathing—to improve tumor oxygenation and radiosensitivity. []
In a phase 3 laryngeal cancer trial, accelerated radiotherapy with carbogen and nicotinamide did not improve 5-year local tumor control compared with accelerated radiotherapy alone, but it was associated with improved regional control without increased toxicity. []
Related: Can B vitamins alter the course of Alzheimer's disease?Where this fits in the longevity conversation
This is where patient-facing supplement language can become confusing. Nicotinamide and niacinamide are the same compound; both are forms of vitamin B3. [] NIH’s Office of Dietary Supplements notes that niacin is the generic name for nicotinic acid, nicotinamide, and related compounds, such as nicotinamide riboside. []
Outside oncology, NAD+ has become a major target in the longevity supplement market. Products containing nicotinamide riboside, nicotinamide mononucleotide, nicotinamide, or other vitamin B3 derivatives are often marketed for “cellular energy,” mitochondrial health, healthy aging, or fatigue.
The rationale is biologically plausible: NAD+ is involved in redox reactions, ATP production, DNA repair, and cellular stress responses. NAD+ levels also decline with age in some tissues, which has helped drive interest in NAD+-boosting supplements. [][]
But in cancer, that biology is not selectively beneficial to healthy cells. Malignant cells also rely on NAD+ metabolism to support proliferation, DNA repair, oxidative stress tolerance, and survival under treatment pressure. That makes anti-aging supplement use clinically relevant. A patient may not think to report “cancer-related” supplements, but may be taking nicotinamide riboside, NMN, niacinamide, or an “NAD+ booster” as part of a longevity or energy regimen.
Of course, this is different from dermatology-guided nicotinamide chemoprevention. A patient taking nicotinamide 500 mg twice daily after recurrent cSCC is not the same scenario as a patient with active pancreatic cancer taking multiple NAD+-boosting products during chemotherapy.
The clinical takeaway is not that every NAD+ precursor is contraindicated in every patient with cancer. Rather, NAD+ boosters should be specifically included in supplement reconciliation, particularly for patients receiving cytotoxic chemotherapy, radiation therapy, or other treatments that rely in part on oxidative stress, DNA damage, or metabolic vulnerability.
A practical phrasing for clinicians may be: “Are you taking anything marketed for anti-aging, cellular energy, mitochondrial support, NAD+, NMN, or nicotinamide riboside?” That question may capture exposures patients would not otherwise think to disclose.
But in cancer, NAD+ biology cuts both ways: Malignant cells can upregulate NAD+ biosynthesis pathways to support proliferation, metabolic reprogramming, DNA repair, and survival under stress. []
Reviews of NAD+ metabolism increasingly frame NAD+ synthesis and salvage pathways as potential therapeutic targets in cancer, rather than universally beneficial pathways to boost. []
That distinction matters because supplement use may occur outside oncology supervision, at doses and combinations not studied in active cancer care.
Consider recent pancreatic cancer research from Case Western Reserve University: Investigators reported that common NAD+ precursor supplements—including nicotinamide mononucleotide, nicotinamide riboside, and nicotinamide—may help pancreatic cancer cells survive and resist treatment in laboratory and mouse models. [] []
The researchers specifically found that these supplements, particularly NMN, shielded pancreatic cancer cells from oxaliplatin, 5-fluorouracil, and gemcitabine by boosting cancer cell energy, reducing oxidative stress, and suppressing DNA damage and cell death. [] []
“Our findings highlight a potentially concerning role for NAD+-boosting supplements in the context of an active cancer, especially when used in conjunction with chemotherapy,” said study lead Jordan Winter, MD, in a press release. “This research is a critical reminder that ‘natural’ doesn’t always mean safe, especially in the complex biology of cancer treatment.” []
That study does not mean nicotinamide is unsafe for all patients, nor does it overturn the skin cancer prevention data. It does, however, sharpen a counseling point: In patients with active cancer—especially those receiving chemotherapy—vitamin B3 derivatives marketed as “NAD boosters,” “anti-aging” supplements, or energy supports should not be treated as benign by default.
Your takeaway
Patients may not recognize that “niacinamide,” “nicotinamide,” “nicotinamide riboside,” “NMN,” and “NAD+ boosters” belong to overlapping supplement conversations.
A patient taking nicotinamide under dermatology guidance for recurrent cSCC risk may be making a different risk-benefit decision than a patient with pancreatic cancer self-starting high-dose NAD+ precursors during chemotherapy.
Nicotinamide remains a reasonable, evidence-supported option to discuss for selected patients at high risk of nonmelanoma skin cancer. But in active oncology care, the same metabolic pathways that make NAD+ attractive in wellness marketing may also be pathways cancer cells exploit.