Does Red Light Therapy Work for Skin Like Yours? Who Was Tested

Red light therapy can smooth fine lines and wrinkles a little, but only after weeks of regular sessions, and the gains in trials were modest. The evidence is thinner than the ads suggest, and trials of light treatments mostly left out the women most likely to get dark spots from them.

You've seen the before and after photos and the glowing masks, and you want to know whether the studies behind them apply to your face. That depends on who was in them. Most skin trials were small, many were paid for by device makers, and few included the darkest skin tones.

Does Red Light Therapy Work for Wrinkles?

It seems to help a little. The best trials found measurable but modest smoothing of fine lines after four to fifteen weeks of sessions.

A 2018 review of 31 randomized LED trials in dermatology looked at six on skin rejuvenation. It gave them a grade C recommendation, below acne and wound healing. The authors said the best results for wrinkles came from daily near-infrared plus red LED light for 8 to 10 weeks. That schedule came from a trial of near-infrared alone, though.

The same review flagged small samples, missing blinding, no sham light in some trials and treatment settings that varied. Two of its authors reported sitting on a company's scientific advisory board, and the review also had NIH funding.

Here are three trials that get cited most often, and who took part in each.

Trial	Who took part	How it was run	What changed
Germany, 2014	136 adults aged 27 to 79, mostly women; skin type not recorded	30 sessions, twice a week; untreated controls, not randomized	Smoother skin and more collagen on ultrasound
Korea, 2007	76 adults with facial wrinkles; sex and skin type not given in the abstract	Half the face, twice a week for 4 weeks; sham light group	Wrinkles down by up to 36% from baseline
2023 trial	137 women aged 40 to 65; skin phototypes II to IV	Red on one side of the face, amber on the other; 10 sessions over 4 weeks	Wrinkle volume around the eyes down about 30%

Who Was Studied in the Red Light Skin Trials?

Mostly women, in small trials, and the darkest skin types were rarely included. Each of the three trials above has a catch worth knowing.

The German trial enrolled 136 volunteers, and 98 of the 128 who finished were women. The 23 controls were mostly employees of the sponsor's company and weren't randomized, and nobody got a sham light. The study was fully funded by JK-Holding, which supplied the lamps, and the lead investigator was paid by the sponsor.

Those lamps were gas discharge lamps, not LEDs. So this trial tells you nothing direct about LED masks. It didn't report skin types either.

The Korean trial, from researchers at Korea University, had a sham light group and treated one side of each face. Its abstract reports wrinkle gains against baseline, though, and doesn't break down sex or skin type.

The 2023 trial enrolled only women aged 40 to 65, with skin phototypes II to IV. Both sides of each face got a light, red or amber, and amber did almost as well as red. Neither color improved hydration or elasticity.

Were Darker Skin Tones Included in the Trials?

Rarely. None of the three trials above clearly included the darkest skin types, phototypes V and VI.

That gap runs across the whole field. A 2023 systematic review of 461 randomized trials of laser and light treatments for cosmetic skin concerns found that 345 reported skin phototype. Of those, only 27.5% included anyone with phototype V or VI.

This matters because the risk isn't the same for everyone. The American Academy of Dermatology (AAD) says darker skin tones are more sensitive to visible light, such as red light. It says the resulting dark spots can be more intense and longer lasting than spots caused by sunlight.

So if your skin is brown or Black, the wrinkle results above were mostly measured on skin lighter than yours. The risk of new dark spots wasn't really tested either. Red light therapy for hyperpigmentation goes through that risk in detail.

Does Red Light Therapy Tighten Sagging Skin?

The evidence is mixed. The Korean trial reported skin elasticity up by as much as 19% from baseline. The 2023 trial of 137 women found no improvement in elasticity with either red or amber light.

Firmer skin is a common promise in the ads. Nothing in these trials shows red light lifting skin that has visibly sagged.

Does Red Light Therapy Work for Acne?

It may calm some red, inflamed pimples, but the proof is weak. Most of the acne evidence is for blue light rather than red alone.

The 2018 LED review gave acne a grade B, based on eight trials. Most of them used blue light, alone or paired with red. In one small trial of 20 people that compared the two, lesion counts fell 71.4% with blue light and 19.5% with red.

A Cochrane review pooled 71 studies with 4,211 participants on light therapies for acne. Most had mild to moderate acne, with an average age of 20 to 30. The studies were small, more than half were industry sponsored, and the reviewers concluded that high-quality evidence is lacking.

Red light therapy for acne explains which kinds of breakouts respond and which won't.

Does Red Light Therapy Help Dark Spots or Discoloration?

Maybe, but the evidence is thin, and it can make things worse on darker skin. In one study the AAD describes, patients said their dark spots looked lighter. That was their own view, not a measured change. The AAD also warns that red light can cause dark spots on darker skin tones.

If fading discoloration is your main goal, the hyperpigmentation article above covers sunscreen and the fading ingredients the AAD recommends instead.

What Results Can You Expect From Red Light Therapy at Home?

Subtle ones, if any. The AAD says red light LED devices can produce subtle to noticeable results on the face, and that not everyone sees them.

The AAD describes one study where 90 patients had 8 red LED treatments to the face over 4 weeks. More than 90% reported some improvement. That was the patients' own view, though, not a measured change.

The AAD also says the red light dermatologists offer is more powerful than home devices, which cost about $100 to more than $1,000. The AAD says it's difficult to know how effective at-home devices are, and FDA clearance says nothing about effectiveness. At-home red light therapy: the numbers on the box covers specs, FDA clearance and eye safety. For schedules, see how often to use red light therapy.

The same questions about who was studied apply to your scalp. Red light therapy for hair growth looks at the hair trials.

Is Red Light Therapy Safe for Your Skin?

The AAD says research hasn't found that red light causes any type of cancer. It also says nobody knows the long-term effects on skin.

The AAD advises seeing a board-certified dermatologist before using red light at home. That matters most if:

• You have lupus or another condition that makes skin sensitive to light. The AAD says it can worsen with red light.
• You take a medication that makes you more sensitive to light. Ask your pharmacist if you aren't sure.
• You have medium to deep skin, or you already get dark marks easily.
• You want to treat a spot or rash that nobody has diagnosed.

The AAD says to wear eye protection if the directions call for it, using the eye protection recommended. Don't substitute sunglasses for protective goggles.

Stop using the device and see a doctor if your skin burns, blisters or stays sore after a session. See a dermatologist if new dark patches appear or keep spreading. Have a dermatologist look at any new or changing spot first.

Frequently Asked Questions

How Long Does Red Light Therapy Take to Work on Skin?

Expect weeks to months. The trials ran from 4 weeks of twice weekly sessions to 30 sessions over about 15 weeks. The AAD says results take time, and not everyone sees them.

Can Red Light Therapy Cause Skin Cancer?

The AAD says research hasn't found that red light causes any type of cancer. Long-term effects on skin are still unknown. The AAD advises seeing a board-certified dermatologist before using a device at home, and following the directions on eye protection.

Is an LED Mask the Same as What Was Tested in Trials?

Not always. The German wrinkle trial used gas discharge lamps, not LEDs. Home devices are also weaker than clinic ones, and the AAD says it's hard to know how well they work.