"Red and blue light are the most commonly used LED lights for skin therapy," says Sejal Shah, MD, a board-certified dermatologist based in New York City. "Yellow and green have not been as well studied but have also been used for skin treatments," she explains, and adds that the combination of blue and red light used at the same time is a "specialized treatment known as photodynamic therapy," or PDT.
This color has been shown to "stimulate collagen production, reduce inflammation, and increase blood circulation," Dr. Shah says, "so it is primarily used for [fine lines and wrinkles] and wound healing." In terms of the former, because it boosts collagen, "red light is thought to [address] fine lines and wrinkles," Dr. Farber explains.
Because of its healing properties, it may also be used as an add-on after other in-office procedures, such as laser or microneedling, to reduce inflammation and recovery time, Shah says. According to aesthetician Joanna Vargas, this means she can perform "an intense peel on someone that can normally leave [their skin] red for hours, but then use infrared afterward and they walk out not red at all."
Red light therapy may also help ease inflammatory skin conditions like rosacea and psoriasis.
"There is encouraging evidence that blue LED light can alter the microbiome of the skin to improve acne," says Dr. Belkin. Specifically, studies have shown that with continued use, blue LED light can help kill acne-causing bacteria and also reduce oil production in the skin's sebaceous glands.
The various light colors may work to differing degrees, says Bruce Brod, a clinical professor of dermatology at the University of Pennsylvania. "Clinical studies [are] relatively consistent in showing a reduction in acne bumps when [blue light] is used regularly," he says. What we know for now, according to Dr. Brod, is that blue light has a "mild benefit for certain types of acne."
As noted, yellow (or amber) LED light hasn't yet been as well-studied as the others, but Dr. Belkin says it "can help reduce redness and healing time." According to Cleveland Clinic, it can penetrate the skin at a deeper depth than its counterparts, and research has demonstrated its efficacy as a supplemental treatment to red LED light in helping to fade fine lines.
"In-office treatments are stronger and better controlled to achieve more consistent results," Dr. Farber says. While the protocol for office treatments vary based on skin concerns, Dr. Shah says in general, LED light therapy lasts approximately 15 to 30 minutes per session and is performed one to three times per week for 12 to 16 weeks, "after which maintenance treatments are usually recommended." Seeing a professional also means a more tailored approach; targeting specific skin concerns, expert guidance along the way, etc.
Though in-office treatments are stronger, "at-home treatments can be quite easy and convenient, as long as proper precautions are taken," Dr. Farber says. Such proper precautions include, as always, following the directions of whatever at-home LED light therapy device you choose to invest in.
