Skin appearance
Red and near-infrared light: wrinkles, roughness and collagen density
Wunsch & Matuschka · 2014 · Photomedicine and Laser Surgery
Wunsch A, Matuschka K. A controlled trial to determine the efficacy of red and near-infrared light treatment in patient satisfaction, reduction of fine lines, wrinkles, skin roughness, and intradermal collagen density increase. Photomed Laser Surg. 2014;32(2):93-100.
What they found
Over 30 sessions, treated groups showed significantly increased ultrasound-measured intradermal collagen density and reduced profilometry roughness versus untreated controls. Blinded photo review rated 69-75% of treated subjects improved versus 4% of controls.
Evidence grade
moderate
Effect direction
positive
Panel relevance
panel replicable
Key outcomes
- Collagen intensity score rose +5.75 (red) and +6.40 (red+NIR) vs -0.26 in controls (p<0.001)
- Skin roughness (Ra) fell -1.79 / -1.58 vs +0.95 (worsening) in controls
- Blinded photographs: 69-75% of treated improved vs 4% of controls
- High patient satisfaction across treated groups
Protocol details
| Device | Filtered low-pressure (red, 611-650 nm) and medium-pressure (red+NIR, 570-850 nm) gas-discharge lamp panels/cabins - not LEDs |
|---|---|
| Wavelengths | 611, 633, 650, 830, 850 nm |
| Irradiance | 5.9-13.3 mW/cm2 (measured in the 611-650 nm band) |
| Dose (fluence) | 8.5-9.6 J/cm2 per session (611-650 nm band) |
| Session time | 20 minutes |
| Frequency | 2x per week |
| Sessions / course | 30 sessions |
| Study length | ~15 weeks (30 sessions) |
| Treatment area | Whole body / face (light cabins and panels) |
| Distance | Whole-body cabin/panel exposure (working distance not specified) |
| Study size | 136 enrolled; 113 randomized to four light groups (two red, two red+NIR) plus 23 untreated controls; 128 completed |
Caveats
- Devices were filtered gas-discharge lamp panels/cabins, not LED panels, though the wavelengths overlap with red/NIR LED devices.
- Per-session dose was modest (~8.5-9.6 J/cm2 in the red band) delivered at low irradiance (5.9-13.3 mW/cm2).
- Lead author has professional ties to the light-technology field - a potential source of bias.
- Outcomes are skin-appearance measures, not treatment of any medical condition.