NMN vs Vitamin C for skin & hair
Short answer: For skin & hair, users rate them about the same: 100% report improvement with NMN (14 reports) and 97% with Vitamin C (29 reports).
NMN has 11 meta-analyses and 17 randomized trials on PubMed; Vitamin C has 738 and 2,072.
Based on 366 reports about NMN and 928 about Vitamin C. Not medical advice.
| NMN Supplement | Vitamin C Supplement | |
|---|---|---|
| Users say it helped | 61%helped113 reports · high confidence | 64%helped204 reports · high confidence |
| Verdict | Mostly positive | Mostly positive |
| Research | AResearch: Strong | AResearch: Strong |
| Meta-analyses / RCTs | 11 / 17 | 738 / 2,072 |
| Mainly used for | ||
| Energy % reporting improvement | 92% (77) | 94% (34) |
| Skin & hair % reporting improvement | 100% (14) | 97% (29) |
| Immunity % reporting improvement | 100% (2) | 90% (40) |
| Mood % reporting improvement | 100% (13) | 88% (25) |
| Sleep % reporting improvement | 65% (20) | 73% (15) |
| Common side effects | insomnia, jitteriness, drowsiness, elevated blood | kidney stones, stomach issues, insomnia, bone pain |
| Typical dose reported | 1 g / daily | 2000 mg / daily |
Overall, NAD⁺ augmentation shows clear biological activity, but clinical effectiveness for anti-aging or wellness outcomes remains inconclusive. Larger, well-designed randomized trials with longer follow-up and prespecified clinically meaningful endpoints are needed, particularly for parenteral approaches.
Ageing Res Rev, 2026 ↗“I've been using NMN for 3 years now, and I had great results with it along with many other supplements. I'm 47 and I look a lot younger and healthier than when I first started NMN.”
The failure of vitamin C supplementation to reduce the incidence of colds in the general population indicates that routine vitamin C supplementation is not justified, yet vitamin C may be useful for people exposed to brief periods of severe physical exercise. Regular supplementation trials have shown that vitamin C reduces the duration of colds, but this was not replicated in the few therapeutic trials that have been carried out. Nevertheless, given the consistent effect of vitamin C on the duration and severity of colds in the regular supplementation studies, and the low cost and safety, it m
Cochrane Database Syst Rev, 2013 ↗“I know people say you get enough vitamin C from diet but I feel and look better when I supplement it.”
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Percentages come from first-hand user reports and are not clinical outcomes. Talk to a doctor before starting, stopping or combining anything. How we rate