Nicotinamide (vitamin B3)
a cheap form of vitamin B3, not the same as NAD+ boosters. Longevity & fitness.
- Verdict
- May lower riskSome studies point to lower risk, but it isn't confirmed.
- How sure
- Rung 2 · LimitedFew, small or conflicting human studies, or only indirect measures such as blood markers.
- How big
- 23% fewer new non-melanoma skin cancers over 12 months in ONTRAC, in people at high risk.
The rung shows how sure the science is, not how big the effect is. How to read these ratings
Cancers affected
Non-melanoma skin cancer, in people who've had several
What the evidence shows
In the ONTRAC trial of 386 people who'd had at least two skin cancers in five years, 500 mg nicotinamide tablets for 12 months meant 23% fewer new non-melanoma skin cancers; the benefit faded once people stopped. A 2023 trial in 158 organ-transplant recipients found no benefit.
What to do
Only relevant if you've had several non-melanoma skin cancers: ask your dermatologist. It doesn't replace sun protection or skin checks.
Sources
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Related
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