Research · Light, skin and health

Types of light therapy: what each does, and what studies show.

Red masks, lasers, flash lamps, ultraviolet booths and light-activated medicines are all called light therapy, but they are different treatments with different evidence. This guide reads recent reviews and trials, separates strong evidence from weak, and covers side effects. Every claim cites its source.

A foot and ankle lit by red, green and violet beams from a light treatment device

365 people
Participants across 8 studies of at-home LED devices, which were associated with improved wrinkles, texture and elasticity. Protocols varied.¹
1,233 patients
In 7 trials of photodynamic therapy versus cryotherapy for actinic keratosis, which cleared lesions about equally well.⁶
95 women
In a sham-controlled red LED mask trial. Blinded specialists scoring photographs found no significant difference.²
Low to moderate
The certainty of evidence for laser and IPL on rosacea redness and visible vessels in a GRADE-rated review.¹¹

The short answer

“Light therapy” is many treatments. LED panels, lasers, IPL, UVB and photodynamic therapy target different things in skin, and results for one do not carry over to another.¹⁰⁷⁵
The best-supported uses are medical. Narrowband UVB is a first-line option for several skin diseases,⁷ and photodynamic therapy clears actinic keratosis about as well as cryotherapy.⁶
Beauty claims are mixed. Reviews report improved wrinkles and texture from LED devices,¹ but a sham-controlled trial found no difference on its main blinded score.²
Side effects vary a lot. Home LED devices had mild ones, while burning, pigment change and blistering were reported with PDT and some IPL and laser protocols.¹⁶¹⁵¹⁴

01 · Six families

Same word, different treatments.

Dermatologic lasers rely on selective photothermolysis, in which light is absorbed by melanin, hemoglobin or water to heat a specific target. A 2026 engineering-to-clinical review sorts lasers by what they treat: Q-switched and picosecond lasers for tattoos and lentigines, pulsed dye and long-pulsed Nd:YAG for vascular lesions, alexandrite and diode for hair removal, and fractional CO₂ and Er:YAG for scars and rejuvenation.¹⁰

LED and ultraviolet devices work differently and are studied for different problems, so the first question to ask about any light device is which kind it is.³⁷

A soft band of pastel refracted light across cream linen beside a clear glass prism

LED and red light
Red and near-infrared, plus blue
Home and clinic panels and masks. Studied for wrinkles, texture and elasticity,¹² and for acne with blue and red light.³⁴
LED and red light in depth
Lasers
Single-wavelength, in clinic
Selective photothermolysis targets melanin, hemoglobin or water. Different lasers are used for tattoos, vessels, hair, scars and rejuvenation.¹⁰
Lasers in depth
Intense pulsed light
Broad-spectrum flash, in clinic
Studied for redness, visible vessels and post-acne erythema, where narrow-spectrum IPL was favoured over broad-spectrum in one comparison.¹¹¹²¹⁵
Intense pulsed light in depth
Narrowband UVB
Ultraviolet, medical
A first-line option for psoriasis, vitiligo, atopic dermatitis, early mycosis fungoides and photodermatoses, according to a 2026 update.⁷
Narrowband UVB in depth
Photodynamic therapy
Light plus a medicine
A topical medicine is activated by light. It cleared actinic keratosis about as well as cryotherapy and was rated better cosmetically.⁶ LED-based versions were reviewed for photoaging and scars.⁵
Photodynamic therapy in depth
Cold plasma
Ionized gas, emerging
Not light in the usual sense. A 2026 review reports faster healing and lower microbial load in trials on chronic wounds, with standardization still unsolved.¹⁷
Cold plasma in depth

02 · LED and red light

The home option, examined.

For wrinkles and texture

A 2026 systematic review of 8 studies and 365 participants found at-home LED devices, with wavelengths from 440 to 1072 nm and red and near-infrared most common, were associated with significant improvements in wrinkles, texture, elasticity and crow’s feet, with high satisfaction.¹
The authors say protocols varied, comparative data were limited and diverse skin tones were underrepresented, and they call for larger standardized trials.¹

The sham-controlled trial

In 95 women aged 45 to 60, a red LED mask (660 nm) used two or three times a week for four weeks did not change the blinded specialists’ wrinkle scale versus sham.²
Image analysis found shorter glabellar and right periorbital wrinkles, and satisfaction was higher than sham, at 79.6% and 73.4%.²
Two sessions a week produced similar results to three.²

For acne

A 2022 meta-analysis of 31 studies found red and blue LED light played an important role in treating acne, with a pooled effect of −2.42.³
A UK analysis rated combined blue and red light among the most cost-effective treatments for mild-to-moderate acne, with wide uncertainty.⁴
A 2026 review calls the benefit of light-based systems modest in mild disease.¹⁶

Other uses, weaker evidence

The same meta-analysis reported benefit from yellow and near-infrared LEDs for herpes simplex and psoriasis lesions and for rejuvenation.³
Results for wound healing and atopic dermatitis were highly inconsistent (I² 85% and 90%).³

How to read this. The reviews are encouraging for red and near-infrared LED, and the one sham-controlled trial is mixed. Both agree that more standardized trials are needed.¹²

03 · Lasers and intense pulsed light

Clinic tools, matched to a target.

The same review stresses that settings matter as much as the device: pulse duration, fluence and spot size are adjusted to the skin type and the treatment endpoint.¹⁰

Redness and vessels. A GRADE-rated review of rosacea trials found low-to-moderate-certainty evidence for laser and IPL on erythema and mainly telangiectasia.¹¹ A 2026 review found pulsed dye laser or IPL improved telangiectasias linked to systemic sclerosis or lupus in all 10 studies it included, although more sessions may be needed.¹²

Post-acne redness. Among 9 randomized trials, picosecond alexandrite laser and narrow-spectrum IPL showed favourable effects against untreated skin, and narrow-spectrum IPL was favoured over broad-spectrum IPL. Small samples and short follow-up prevented the authors naming a preferred treatment.¹⁵

Photoaging. In a retrospective study of 50 patients with Fitzpatrick types III to IV, three monthly Q-switched 1064 nm sessions lowered the mean wrinkle score from 4.54 to 3.42. The authors note there was no control group.¹³

Melasma. A 2026 review says IPL, photobiomodulation and several lasers show promise but no single modality is definitive. Combinations with topical or oral agents work better, and maintenance is crucial.¹⁴

A warm rose and amber glow of light softly diffused through sheer cream silk

04 · Ultraviolet and photodynamic therapy

The strongest evidence is for disease.

Narrowband UVB

A 2026 update from a group of Latin American and Spanish dermatologists says it remains first-line for psoriasis, vitiligo, atopic dermatitis, early mycosis fungoides and photodermatoses, on efficacy, safety and cost-effectiveness.⁷
For mycosis fungoides, a Cochrane review notes PUVA is commonly recommended first-line. It also found a lack of high-certainty evidence in that field.⁹
Treatment is given under medical supervision with eye protection.⁸

Photodynamic therapy

Across 7 trials and 1,233 patients, PDT and cryotherapy cleared actinic keratosis similarly (RR 1.02). Cosmetic outcome was better with PDT (74.62% vs 49.11%).⁶
PDT caused significantly more burning and pain. Cryotherapy caused more vesicles and blisters.⁶
A review of 24 articles found LED-activated PDT with MAL or 5-ALA was associated with smoother texture, fewer rhytides and improved scars, but high-quality studies were scarce.⁵

05 · Beyond skin

Light and the rest of health.

A 2026 summary of the year’s primary-care research lists bright light therapy as effective for nonseasonal depression.¹⁸ That is a different treatment from the skin devices on this page and it is delivered by a different kind of lamp.

In 30 dermatology patients having narrowband UVB, sleep quality and fatigue improved over a month, while dermatology quality of life did not change. It was an observational pilot, so it cannot show that the light caused the change.⁸

Cold atmospheric plasma is an ionized gas, not a lamp, and sits at the edge of the light family. A 2026 systematic review reports randomized trials in chronic wounds with faster healing and lower microbial load, and notes unsolved standardization and dosing.¹⁷

Ron Ignatius holding a glowing red light wand up to his hand in front of a pink-lit plant growth cabinet

Special mention

Ron Ignatius and the LED that grew potatoes.

Ron Ignatius was an engineer who studied LEDs for growing plants in space, and founded Quantum Devices in 1989. NASA small-business grants helped his company build an LED plant-growth unit that grew potatoes on the space shuttle in 1995.¹⁹

He then became interested in medical uses of the same lights and contacted a Medical College of Wisconsin neurologist researching light therapy. His company went on to develop handheld LED devices, and the FDA cleared one for temporary relief of minor muscle and joint pain.¹⁹ The technology was inducted into the Space Technology Hall of Fame in 2000, and Ron Ignatius is among the individuals listed for it.²⁰

Read the full story

The Accidental Discovery of Redlight Therapy

Our research book follows the history from Niels Finsen’s 1903 Nobel Prize to the NASA-funded LED work, and asks how much of it is proven and how much is marketing.

Read the book

06 · Evidence at a glance

What kind of evidence is this?

The bars sort the 18 research sources on this page by study type. Most are reviews, and one is a randomized, sham-controlled trial on a home light device.

Systematic reviews and meta-analyses8Pooled or summarized trials^{1, 3, 5, 6, 9, 11, 15, 17}
Narrative reviews and guidance5Expert overviews of the field^{7, 10, 12, 14, 16}
Observational and retrospective studies2No control group^{8, 13}
One randomized, sham-controlled trial195 women, red LED mask²
Cost model1Built from a network meta-analysis⁴
Primary-care summary1Bright light for depression¹⁸

Studies on light therapy: what was studied, the type of study, what was measured and the result
What was studied	Study type	What was measured	Result
95 women aged 45 to 60, red LED mask (660 nm), 4 weeks	Human: randomized, sham-controlled	Wrinkle scale by blinded specialists, wrinkle length by image analysis, satisfaction	No significant difference on the wrinkle scale. Image analysis found shorter glabellar and right periorbital wrinkles. Satisfaction was 79.6% and 73.4% in the treated groups. Two sessions a week seemed enough.²
8 studies, 365 participants, at-home LED devices	Human: systematic review	Wrinkles, texture, elasticity, satisfaction, side effects	Significant improvements, mostly with red and near-infrared light. Side effects were infrequent, mild and transient. The authors note varied protocols and few diverse skin tones.¹
50 patients, Fitzpatrick III–IV, Q-switched 1064 nm laser, 3 sessions	Human: retrospective, no control	Wrinkle and elastosis scale, pain, side effects	Mean score fell from 4.54 to 3.42. Mild transient redness in four patients. The authors flag the lack of a control group.¹³
7 trials, 1,233 patients, actinic keratosis	Human: meta-analysis	Lesion clearance, cosmetic outcome, side effects	Clearance was similar to cryotherapy (RR 1.02). Cosmetic outcomes were better with PDT (74.62% vs 49.11%), and burning and pain were more frequent.⁶
9 randomized trials, 301 participants, post-acne erythema	Human: systematic review	Redness, safety	Picosecond alexandrite laser and narrow-spectrum IPL showed favourable effects. Trials were small and short, so no preferred treatment could be named.¹⁵
30 patients on narrowband UVB, mostly vitiligo, mycosis fungoides and psoriasis	Human: observational pilot	Sleep quality, fatigue, dermatology quality of life	Sleep scores improved from a median of 8 to 5 and fatigue from 3.88 to 2.38 after one month. Quality-of-life scores did not change.⁸

07 · Safety

Gentle, or not, depending on the light.

Home LED

Adverse events were infrequent, mild and transient across the 8 studies reviewed, but the review notes diverse skin tones were underrepresented.¹

PDT, IPL and lasers

PDT caused more burning and pain than cryotherapy.⁶ One broad-spectrum IPL protocol caused pigmentation and blistering.¹⁵ Laser treatment of melasma carries a risk of post-inflammatory hyperpigmentation, especially in darker skin.¹⁴

Ultraviolet

Narrowband UVB is given with eye protection in clinic.⁸ The update recommends using it within a supervised treatment plan.⁷

An honest limit. None of the sources we read tested eye safety for home masks, and we make no safety claim about any specific device. Skin type, medicines and conditions all change the risk, so ask a clinician.

08 · Reading a claim

Five questions to ask of any light device.

Which kind of light is it?
An LED mask, a laser, a flash lamp and a UV booth are different treatments.¹⁰⁷¹ “Light therapy” alone does not say.
Was there a sham group?
The trial with a sham mask found no difference on its blinded wrinkle scale.² Studies without a control cannot separate the light from other changes.¹³
Who judged the result?
The same trial found different answers from blinded specialists, from image software and from participants’ satisfaction.² Check which one a claim uses.
Does it match your skin tone?
Reviews flag underrepresentation of diverse skin tones,¹ and settings are chosen by skin type.¹⁰
Is the use medical or cosmetic?
The firmest evidence here is for diseases such as psoriasis, vitiligo and actinic keratosis.⁷⁶ Cosmetic evidence is thinner and more mixed.¹²

09 · What we could not confirm

The gaps, stated plainly.

Percentage figures for acne, hair removal, wound healing or psoriasis clearance quoted in the reference documents we were given. We did not find them in the records we read, so we did not use them.
Best wavelengths, doses, session counts and penetration depths for any skin goal. The studies vary too much to name one.¹
Which home devices are cleared or approved by a regulator, and any recalls. We did not verify device-by-device status, so we make no claim.
Long-term safety of home LED and IPL use, including eye safety for masks.
Benefit of any light therapy on hair loss, cellulite, muscle recovery or pain. We did not review these.
Head-to-head comparisons of LED, laser and IPL for the same wrinkle or pigment goal.¹⁵

Vanu Health’s DermaGlass® masks are hydrating skincare, not light devices. This page makes no light therapy, anti-aging, acne or pain claim about them or any other Vanu Health product.

10 · Questions

Frequently asked questions.

What are the main types of light therapy for skin?

The sources we read cover LED and photobiomodulation (red and near-infrared light, plus blue), lasers, intense pulsed light, narrowband UVB phototherapy, photodynamic therapy (a light-activated medicine) and, less commonly, cold atmospheric plasma. They differ in wavelength, in what they target and in how strong the evidence is for each use. ^{1, 3, 7, 10, 5, 17}

Does red light therapy reduce wrinkles?

Some evidence says yes, with limits. A 2026 systematic review of 8 studies and 365 participants found at-home LED devices, mostly red and near-infrared, were associated with improvements in wrinkles, texture and elasticity, with mild side effects. But in a sham-controlled trial of 95 women using a red LED mask, blinded specialists scoring photographs found no significant difference, while image analysis found shorter wrinkles in two areas. ^{1, 2}

Does blue light clear acne?

A 2022 meta-analysis found red and blue LED light significantly helped acne. A UK cost-effectiveness analysis found combined blue and red light among the most cost-effective options for mild-to-moderate acne, with wide uncertainty. A 2026 review judged light-based systems to give modest benefit in mild disease. ^{3, 4, 16}

Is light therapy safe?

It depends on the type. At-home LED devices had infrequent, mild and transient side effects in the studies reviewed. Photodynamic therapy caused more burning and pain than cryotherapy. One broad-spectrum IPL protocol caused pigmentation and blistering, and lasers for melasma carry a risk of post-inflammatory pigmentation, especially in darker skin. UV phototherapy is given with eye protection. We found no source that tested eye safety for home masks. ^{1, 6, 15, 14, 8}

Can light therapy help with depression or sleep?

A 2026 summary of primary-care research lists bright light therapy as effective for nonseasonal depression. A 30-patient pilot study found sleep scores improved during narrowband UVB treatment for skin disease. That was an observational pilot with no control group, so it cannot show cause. ^{18, 8}

Which light therapy is best for rosacea or visible veins?

A 2019 systematic review found low-to-moderate-certainty evidence for laser and intense pulsed light for rosacea erythema and mainly telangiectasia. A 2026 review found pulsed dye laser or IPL improved telangiectasias in patients with systemic sclerosis or lupus in all 10 studies it included, with more sessions possibly needed. ^{11, 12}

Does Vanu Health make a light therapy claim?

No. This page reports what published studies say. It makes no light therapy, anti-aging, acne or pain claim about any Vanu Health product.

Keep reading

The Research Desk: every guide and dataset from the same team.
Blue light and skin: what studies show.
The Accidental Discovery of Redlight Therapy: our research book.
Light devices: Vielight, Valeda and Wellscare, with the evidence rated.
Sunlight and skin: UV, visible light and what they do.
Skin whitening: what studies show on pigment.

Blue light and your skin: pigmentation, screens versus sunlight, tinted sunscreen.
Sunlight and skin health: UV, vitamin D, skin aging and skin cancer risk.
Collagen types: types I, III, IV, VII and XVII in skin.
Seasonal skincare: how skin changes across spring, summer, autumn and winter.
The Accidental Discovery of Redlight Therapy: a book from the Vanu Health library.
Research Desk sources: every reference, organised by guide.
The Research Desk: all guides and datasets.

Sources

Where every claim comes from.

Numbers in brackets link to these entries. Sources 1 to 18 were each read as their PubMed record, with the title, journal, date and abstract, and study details come from PubMed, the US National Library of Medicine. Links open the paper through its DOI. Dates are those shown on the source. Sources 19 and 20 are NASA and Space Foundation pages, used only for the Ron Ignatius mention.

All sources across the Research Desk are collected, by page, in the master source list.

[1] Aesthetic Plastic Surgery (Das and colleagues). Efficacy and safety of at-home light-emitting diode photobiomodulation for facial rejuvenation: a systematic review. October 2026.
[2] Lasers in Medical Science (Bragato and colleagues). Role of photobiomodulation application frequency in facial rejuvenation: randomized, sham-controlled, double-blind, clinical trial. April 2025.
[3] Photodermatology, Photoimmunology & Photomedicine (Ngoc and colleagues). Utilization of light-emitting diodes for skin therapy: systematic review and meta-analysis. November 2022.
[4] Clinical and Experimental Dermatology (Mavranezouli and colleagues). Cost-effectiveness of topical pharmacological, oral pharmacological, physical and combined treatments for acne vulgaris. October 2022.
[5] Dermatologic Surgery (Huang and colleagues). Light-emitting diode-based photodynamic therapy for photoaging, scars, and dyspigmentation: a systematic review. November 2020.
[6] Journal of Cosmetic Dermatology (Aldraibi and colleagues). Comparative efficacy of photodynamic therapy versus cryotherapy for actinic keratosis: a systematic review and meta-analysis of randomized controlled trials. April 2026.
[7] Actas Dermo-Sifiliográficas (Carrascosa and colleagues, GEF-CILAD). Narrowband UVB phototherapy in dermatology: GEF-CILAD 2026 update. June 2026.
[8] Sisli Etfal Hastanesi Tip Bulteni (Kaya and colleagues; pilot study of 30 patients). Effects of phototherapy on sleep, fatigue and quality of life in dermatology patients: a pilot study. June 2026.
[9] Cochrane Database of Systematic Reviews (Valipour and colleagues). Interventions for mycosis fungoides. July 2020.
[10] Lasers in Medical Science (Park and colleagues). Strategic selection of multi-parametric laser settings and clinical endpoints in dermatology: an engineering-to-clinical review. June 2026.
[11] British Journal of Dermatology (van Zuuren and colleagues). Interventions for rosacea based on the phenotype approach: an updated systematic review including GRADE assessments. March 2019.
[12] Lasers in Surgery and Medicine (Shah and colleagues). Efficacy of lasers and light sources for telangiectasias in the setting of systemic sclerosis and systemic lupus erythematosus: a review. July 2026.
[13] Lasers in Medical Science (Zappia and colleagues; retrospective study of 50 patients). Use of a nanosecond Q-switched 1064 nm Nd:YAG laser for photoaging management in Asian skin: a retrospective study. August 2026.
[14] Dermatologic Clinics (Campos and colleagues). Lasers for melasma. May 2026.
[15] Cureus (Alhussain and colleagues). Post-acne erythema: a systematic review of randomized controlled trials on the comparative efficacy and safety of interventions across clinical, instrumental, and patient-reported outcomes. September 2026.
[16] Dermatologic Clinics (Haddad). Acne laser devices in dermatology. July 2026.
[17] Infection Prevention in Practice (Namvar Vansofla and colleagues). Cold plasma technology as a novel antimicrobial platform: mechanisms, efficacy, and clinical translation: a systematic literature review. September 2026.
[18] American Family Physician (Ebell and Grad; summary of 2025 patient-oriented studies). Top 20 research studies of 2025 for primary care physicians. August 2026.
[19] NASA Spinoff. NASA research illuminates medical uses of light.
[20] Space Foundation, Space Technology Hall of Fame. Light emitting diodes for medical applications (inducted 2000).

This page is general information from the Vanu Health Research Team. It is not medical advice. The prism and silk-glow images are AI-generated illustrations, not study images. Last updated October 30, 2026.