If you’ve hit your late 30s or 40s and noticed your hair losing a bit of its former swagger: less volume, thickness, shine, and a little more shedding, welcome to the club. Hair isn’t just cosmetic, it’s a visible barometer of how our cells, hormones, and metabolism are doing as we age.
This has led some to ask the question: can NMN, the molecule everyone’s talking about for energy, repair and longevity, actually help with hair? A recent human study from Japan by Mitsubishi Human Life Sciences Limited suggests it’s possible, yes, but with some important caveats.
First: what is NMN and why might it matter for hair?
NMN (nicotinamide mononucleotide) is a precursor to NAD+, the molecule our cells rely on for energy production, DNA repair and mitochondrial function. NAD+ levels fall as we age, and hair follicles are among the most energy‑hungry structures in the body. Therefore, it doesn’t take a genius to deduce that supporting NAD+ might support follicle health.
The Japanese NMN hair study
A small study in Japan tested whether NMN could influence hair quality. Here’s the study’s salient points:
- 15 women, aged 40–50
- 12‑week open‑label design (no placebo)
- 500mg/day NMN
- Measurements: hair thickness, anagen density, terminal hair density, questionnaires
Key Findings:
- Hair shaft thickness increased (approx. 75µm to 79µm)
- Hair‑growth density increased (approx. 56 to 88 hairs/cm²)
- Terminal hairs increased (approx. 39 to 66 hairs/cm²)
- Participants reported improved volume, gloss, strength, and reduced shedding
- Metabolomics suggested improved energy metabolism
- Total hair count decreased, likely seasonal shedding
Limitations:
- Very small sample size (15)
- No control group
- All participants were Japanese women 40–50
- Short duration
- Study funded by a company selling NMN (so let’s assume some bias)
So… does NMN help hair?
The honest answer: it probably helps hair quality and growth‑phase activity, but evidence is early and not conclusive. Results are promising but need larger, controlled, independent trials.
How this fits Uthful’s viewpoint
Supporting NAD+ may support hair health as part of overall vitality. This aligns with Uthful’s message of consistency and cellular resilience. But we won’t claim NMN reverses baldness or prevents you going grey. We’ve heard personal stories of this, but that’s not what this recent study shows.
Realistic expectations
If you’re taking NMN for hair growth you may see gradual improvements in thickness and strength over 2–3 months, especially for age‑related hair changes. (The author has certainly noticed their hair and nails seem to grow faster since they’ve taken NMN). However, until bigger studies are undertaken, it’s best viewed, perhaps, as part of a broader routine including nutrition, stress management, sleep, and overall health.
Source:
“Oral Supplementation of Nicotinamide Mononucleotide (NMN) Improves Hair Quality…” Cosmetics 2025, 12(5), 204.
https://www.mdpi.com/2079-9284/12/5/204
