Fine lines and wrinkles are near the top of the list of uses red light is promoted for, Cleveland Clinic says. The pitch is simple: light builds collagen, and collagen smooths lines.
This article looks at what a controlled trial measured and what dermatologists say about home devices. It sits under our overview of red light therapy benefits. It is general information, not medical advice.
Short answer: one randomized trial of 136 volunteers found that 30 sessions of red light, twice a week, reduced skin roughness and raised collagen density compared with no treatment. Harvard Health, citing the American Academy of Dermatology, says red light may reduce fine lines and wrinkles. However, results take months, and home devices may be weaker than the ones in studies.
What the 2014 trial did
Wunsch and Matuschka (2014) found the most-cited result for skin. Their randomized, controlled trial in Photomedicine and Laser Surgery put 113 volunteers into four light groups and kept 23 as untreated controls. Each treated person had 30 sessions, twice a week, with a dose of about 9 J/cm² in the 611 to 650 nm red range. The trial measured skin with ultrasound, a roughness scanner, and blinded photographs.
| Measure | Result in treated groups vs controls |
|---|---|
| Skin roughness | Lower |
| Collagen density (ultrasound) | Higher |
| Blinded photo grading | Significantly better |
| Red only vs red plus wider spectrum | No advantage for the wider spectrum |
That last row matters for shoppers. Adding a broader range of light, out to 850 nm, did not beat red light alone in this trial.
What dermatologists say
According to Harvard Health’s October 2025 article, the American Academy of Dermatology reports research suggesting red light may “reduce fine lines and wrinkles.” The article’s reviewer, Rachel Reynolds, MD, adds a time frame:
“For the devices to be effective, they must be used multiple times a week for four to six months.”
Rachel Reynolds, MD, Beth Israel Deaconess Medical Center, in Harvard Health, 2025
Cleveland Clinic lists wrinkles, fine lines, and facial texture among the uses red light is promoted for. Its overall view is that studies “show some potential,” but the evidence doesn’t support most uses yet.
Limitations of the evidence
The key trial is a single study with a small control group of 23 people. It used large, full-body light units at a set dose, not a handheld mask. Although the results were positive, a reader can’t assume a different device at a different dose will match them.
Here’s what the spec sheet won’t tell you. The trial’s dose was 9 J/cm². A home device only lets you compare if it publishes its irradiance and the distance it was measured at. Red Light Therapy Wavelengths explains the 660 nm and 850 nm figures you’ll see on listings.
Home device or clinic?
Harvard’s reviewer says over-the-counter devices “may be weaker,” while professional versions can better control the dose. She suggests choosing home devices labeled FDA-cleared. Home masks, caps, and wands typically cost several hundred dollars or more, the article says.
My rule of thumb: plan on 4 months of use before judging any device, and take a dated photo in the same light on day one.
Bottom line: there is trial evidence that red light can improve skin texture and collagen over about 15 weeks of twice-weekly sessions. It’s one trial, and home devices vary. For the other claims, see the red light therapy benefits overview linked above.
Sources
- 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,” Photomedicine and Laser Surgery, 2014 (abstract): pubmed.ncbi.nlm.nih.gov
- Harvard Health Publishing, “Red light therapy for skin care,” October 21, 2025, reviewed by Rachel Reynolds, MD: health.harvard.edu
- Cleveland Clinic, “Red Light Therapy,” medically reviewed December 1, 2021: my.clevelandclinic.org