What Published Studies Say About Red Light and Skin Appearance

Quick answer

Researchers have studied red and near infrared light on facial skin for years. Most of the published work is small, short, and run in clinics with professional devices. Some studies saw differences between light and sham groups on rating scales. Others found that what participants reported did not match what trained raters saw, or that raters saw no difference at all. None of this tells you what a consumer device will do for you or for anyone in particular.

What these studies are, and are not

This page summarizes seven published papers. It is not medical advice, and it does not say that any light device changes how anyone's skin looks. A clinical study uses a specific device, dose, schedule and group of people. Findings from that setting cannot be assumed for a consumer device, for a different dose, or for any one person.

A sham controlled trial of a home use mask

In 2025, Park, Park and Jung published a randomized, double blind, sham controlled trial in the journal Medicine, run at two sites ^[1].

• Who: 60 adults enrolled and 59 analyzed, aged 30 to 65, of Asian descent, skin types II to V, with a score of 2 to 4 on a grading scale for lines at the outer corner of the eye, measured at rest. Most were women.
• Device: a home use helmet style mask with a 630 nm LED and an 850 nm infrared emitting diode, each with a stated maximum of 10 mW per square centimeter in the methods section. The abstract prints the area unit differently, so be careful with the unit.
• Schedule: 9 minutes, 5 times a week, for 12 weeks, with a visit at week 16.
• Comparison: a sham device with the same look, no infrared output, and the red LED at one tenth of the active intensity.
• Measured: an independent rater's grade of the lines from photographs, an investigator's grade, global improvement scales scored by investigators and by participants, and adverse events.

At 12 weeks, 25 of 29 participants in the active group were rated by the independent rater as improved by at least one grade, compared with 5 of 30 in the sham group. Investigator ratings differed between groups from week 8. Participant ratings did not: the authors reported no significant difference between groups on the participant global scale. Four of 60 participants reported an adverse event, and the authors described none as serious.

The authors listed these limits: a short follow up, the possibility that some participants used other skin care during the trial, and no objective measure of the skin brightening that about a quarter of participants noticed. The study was funded by the maker of the device, and the paper states that design, data collection, analysis and writing were independent of the funder. Each group had about 30 people.

A mask trial with a published plan and a published report

A 2023 paper in Medicine by Bragato and colleagues described the plan for a three arm trial of women aged 45 to 60, comparing two weekly schedules of a 660 nm red LED mask with a sham mask over four weeks ^[2]. The plan listed 92 LEDs, each at 6.4 mW per square centimeter at the LED opening, 21 minutes per session, and a target of 108 women. Planned measures included photo scoring by three plastic surgeons, optical coherence tomography of silicone casts of forehead lines, image analysis, and a satisfaction questionnaire. A plan reports no outcomes.

In 2025 the same group published the trial report in Lasers in Medical Science ^[3]. Only the abstract was opened for this page. It reports that 95 women took part, with one group using the mask three times a week, one twice a week, and a control group receiving sham sessions twice a week, for four weeks. The abstract states that the three blinded specialists' rating scale showed no significant differences among the groups. Image software measures showed differences in the length of lines in two of the regions measured, in the light groups compared with control. Satisfaction rates on a questionnaire were 79.6 percent and 73.4 percent in the two light groups, with significant differences against control. The authors reported that the number of sessions per week did not significantly change the satisfaction or photograph assessments taken 30 days after the last session.

The two papers together show how a measure can look different depending on who scores it: specialists using a rating scale, software measuring images, and participants answering a questionnaire.

A split face trial with LED light

A 2007 paper in the Journal of Photochemistry and Photobiology B by Lee and colleagues described a randomized, placebo controlled, double blind study of 76 patients ^[4]. Light was applied to the right half of each face. Participants were assigned to 830 nm light, 633 nm light, both, or a sham light, twice a week for four weeks, with a three month follow up.

The researchers measured photographs, skin surface profile, elasticity, melanin, skin samples under the microscope and several lab markers. The abstract reports changes of up to 36 percent in a skin profile measure and up to 19 percent in elasticity compared with the participants' own starting values, in the three light groups. Those are maximum values, not averages, and they are comparisons with baseline. The abstract does not give the dose, the number of people per group, or the funding. Because those details are missing from the page, this study is a weak basis for any conclusion about everyday use.

Reviews of the wider research

Light plus a drug. A 2020 systematic review in Dermatologic Surgery by Huang, Nguyen and Jagdeo looked at LED light used together with a light sensitive drug applied to the skin, a method called photodynamic therapy ^[5]. It included 24 original articles, searched through May 2019. The authors noted that few high quality studies on cosmetic outcomes were found and called for well designed randomized trials. This is a different method from light alone, so it is not evidence about wearing a mask or standing in front of a panel.

Randomized trials of LEDs across skin topics. A 2018 systematic review in Lasers in Surgery and Medicine by Jagdeo and colleagues reviewed 31 randomized trials of LED light in dermatology ^[6]. Most of it concerns medical skin topics outside the scope of this page. The authors listed limits of some of the studies they reviewed: small samples (fewer than 20 people), no blinding, no sham comparison, and varied light settings.

A pooled analysis. A 2023 systematic review and meta analysis in Photodermatology, Photoimmunology and Photomedicine by Ngoc, Moon and Lee assessed 554 articles and selected 31 studies ^[7]. The authors reported that for some topics the pooled analyses differed a lot from study to study, with heterogeneity values of 85 and 90 percent, which they linked to a lack of unpublished articles. Most of that paper also concerns medical skin topics outside this page.

Limits across these studies

• Small samples and short follow up. Most groups had around 30 people or fewer, and follow up ranged from weeks to a few months.
• Clinic settings. Professional devices, set schedules and trained raters are not the same as home use.
• Funding. At least one study was paid for by the device maker.
• Different scorers, different answers. Raters, image software and participants did not always agree.
• Who was studied. Specific ages, skin types and mostly women. The findings may not apply to you.
• Missing details. Some papers do not report dose in a way that lets you compare them, and for one paper only the abstract was available to check.
• Wide variation. Wavelength, dose, schedule and device differed across studies, so they cannot be stacked into a single answer.
• Publication gaps. This page covers a handful of papers, not the whole field.

Talk to a clinician

If you have a skin concern, a skin condition, a history of skin cancer, or take medicines that make skin sensitive to light, talk to a dermatologist or other licensed clinician before using any light device. This page is not medical advice and does not diagnose anything.

Related reading

For a plain explanation of the colors used in these studies, see our guide to red light vs near infrared vs blue light.

If you are comparing face masks, our checklist of what to check before you buy a red light therapy mask covers specs to compare and questions to ask a seller.

To see how session schedules are usually described, read how often people use red light therapy.

Sources

All pages below were opened and checked on October 15, 2026.

1. Park SH, Park SO, Jung JA. Medicine (Baltimore). 2025;104(7):e41596. PMC
2. Bragato EF, Pires JA, Momolli M, et al. Medicine (Baltimore). 2023;102(5):e32514. Trial plan. PMC
3. Bragato EF, Paisano AF, Pavani C, et al. Lasers Med Sci. 2025;40(1):170. Abstract only. PubMed
4. Lee SY, Park KH, Choi JW, et al. J Photochem Photobiol B. 2007;88(1):51 to 67. Abstract only. PubMed
5. Huang A, Nguyen JK, Jagdeo J. Dermatol Surg. 2020;46(11):1388 to 1394. Abstract only. PubMed
6. Jagdeo J, Austin E, Mamalis A, Wong C, Ho D, Siegel DM. Lasers Surg Med. 2018;50(6):613 to 628. Abstract only. PubMed
7. Ngoc LTN, Moon JY, Lee YC. Photodermatol Photoimmunol Photomed. 2023;39(4):303 to 317. Abstract only. PubMed