Low-power green light aimed at the scalp for thinning hair. Treated scalp areas gained thicker, denser hair over six months in two small studies, both from one team that helped build the devices and neither using a dummy-treated area. Reported harms are mild scalp warmth and redness. Every approved hair-loss device emits red or near-infrared light instead. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Ferritin | 70–100 ng/mL (women), 100–150 ng/mL (men) | Low iron stores prolong the resting phase and cap any regrowth response |
| 25-Hydroxyvitamin D | 40–60 ng/mL | Deficiency is repeatedly associated with pattern and patchy hair loss |
| Thyroid-stimulating hormone (TSH) | 0.5–2.0 mIU/L | Both under- and overactive thyroid cause diffuse shedding that mimics device failure |
| Serum zinc | 90–120 µg/dL | Zinc is required for follicle protein synthesis and is depleted by chronic dieting |
| Dehydroepiandrosterone sulfate (DHEA-S) | 200–400 µg/dL (men), 150–300 µg/dL (women) | Adrenal androgen excess drives follicle shrinkage independently of testicular or ovarian output |
| Trichoscopic hair density at a marked reference point | No established target; change from own baseline, any rise by 24 weeks | The only direct measure of whether the device is doing anything |
Cadence: Laboratory panel at baseline, repeated at three months where any value was abnormal, otherwise at six to twelve months. Photographs and trichoscopic count at 4, 12, and 24 weeks, then every six months. The device is judged at 24 weeks.