Nicotinamide for UV Protection (Internal Photoprotection)
A Strong Evidence Multiple large clinical trials consistently show significant benefits.At chemoprevention doses (1,000 mg/day), oral nicotinamide replenishes UV-depleted NAD+ stores, enhancing cellular energy for DNA repair and supporting immune surveillance of UV-damaged cells (ONTRAC Phase 3 trial).
The Bottom Line
At chemoprevention doses (1,000 mg/day), oral nicotinamide replenishes UV-depleted NAD+ stores, enhancing cellular energy for DNA repair and supporting immune surveillance of UV-damaged cells (ONTRAC Phase 3 trial).
Key Study Findings
Population: Overview of reviews on niacin/nicotinamide adverse effects
Population: High-risk NMSC patients (RCTs)
Population: None
Population: General population (cosmetic users)
Key Statistics
5
Studies
686
Participants
Positive
Grade
Referenced Papers
Dosage & Usage
mg = milligrams · mcg = micrograms (1,000× smaller) · IU = International Units
Commonly Used Dosages
- generalskinbarrier:
- 500-1,500 mg/day
- skincancerchemoprevention:
- 500 mg twice daily (1,000 mg/day total)
Upper limit: Generally well-tolerated up to 3,000 mg/day (no flushing unlike niacin)
Dosages Studied in Research
| Dosage | Duration | Effect | N |
|---|---|---|---|
| None | -- | Mixed | -- |
| Nicotinamide (vitamin B3) | -- | Positive | -- |
| None | -- | Mixed | -- |
| None | -- | Mixed | -- |
| Niacinamide up to 5%; Niacin up to 0.1% | -- | Mixed | -- |
Best taken: With meals; split into 2 doses for chemoprevention
Safety & Side Effects
Reported Side Effects
- ⚠ Generally well-tolerated (no flushing)
- ⚠ Mild gastrointestinal discomfort at high doses
- ⚠ Rare hepatotoxicity at very high doses
Known Interactions
- ● Anticonvulsants (carbamazepine — may increase levels)
- ● Isoniazid (competes for NAD+ pathways)
- ● Hepatotoxic drugs (potential additive liver effect at high doses)
Tolerable upper intake: Generally well-tolerated up to 3,000 mg/day (no flushing unlike niacin)
Always consult your healthcare provider before starting any supplement.
Frequently Asked Questions
Does Nicotinamide help with UV Protection (Internal Photoprotection)?
How much Nicotinamide should I take for UV Protection (Internal Photoprotection)?
Are there side effects of Nicotinamide?
How strong is the evidence for Nicotinamide and UV Protection (Internal Photoprotection)?
Related Evidence
Other ingredients for UV Protection (Internal Photoprotection)
References
- [1] Su Ling Young et al.. Eye (Lond). 2025. The adverse effects of oral niacin/nicotinamide - an overview of reviews. doi:10.1038/s41433-025-04027-2 PubMed
- [2] Giulio Tosti et al.. Nutrients. 2023. The Role of Nicotinamide as Chemo-Preventive Agent in NMSCs: A Systematic Review and Meta-Analysis. doi:10.3390/nu16010100 PubMed
- [3] Katherine G Thompson et al.. J Am Acad Dermatol. 2021. Dietary supplements in dermatology: A review of the evidence for zinc, biotin, vitamin D, nicotinamide, and Polypodium. doi:10.1016/j.jaad.2020.04.123 PubMed
- [4] Reed Huber et al.. Skin Therapy Lett. 2020. Nicotinamide: An Update and Review of Safety & Differences from Niacin. PubMed
- [5] Cosmetic Ingredient Review Expert Panel. Int J Toxicol. 2005. Final report of the safety assessment of niacinamide and niacin. doi:10.1080/10915810500434183 PubMed
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