Red light therapy may be beneficial when it comes to improved skin appearance, wound healing and pain management, according to current research.

Red light therapy uses the therapeutic application of light energy primarily to aid in the healing of skin and muscular conditions, such as scarring and tendonitis. By exposing the body to a low wavelength of red light (620 to 750 nanometers), red light therapy stimulates increased energy production in the cells, which may lead to myriad health benefits.

While there are promising studies suggesting the efficacy of red light therapy, more research is necessary to fully determine its potential benefits. However, it’s already being used with success in many different clinical settings.

Read on to learn more, including potential benefits, side effects and how to use red light therapy.

What Is Red Light Therapy?

When it comes to the discovery of potential benefits of red light therapy, you can actually thank voyages to outer space.

In October 1995, sources of red light—part of the visible spectrum of light—made their space shuttle flight debut on the second U.S. Microgravity Laboratory Spacelab mission (STS-73, Columbia) as part of experiments in plant growth.

“It was here that astronauts tending the plant growth chambers noticed little scratches on their hands began to heal,” says red light therapy researcher Janis T. Eells, Ph.D., a professor in the Department of Biomedical Sciences at the University of Wisconsin-Milwaukee. “Nothing heals in space, so NASA funded many years of research with these lights for human trials.”

These studies led to the discovery that red light therapy could be used deliberately as a type of photomedicine, which is the application of light for health and healing purposes. Visible light penetrates biological tissues, such as cells, muscle tissues and nerve tissues—with red and near-infrared (NIR) light going deeper than green, blue or violet light.

“With red light therapy, you expose an area of your body to a specific wavelength of red light emitted by a device that can range in size from handheld to whole-body,” says Casey Kelley, M.D., founder and medical director of Case Integrative Health. “Essentially, the red light stimulates your cells to work at a higher level.”

How Does Red Light Therapy Work?

Red light therapy works by activating your mitochondria, or the powerhouse of the cell, explains Dr. Kelley. With this boost to the energy center of the cell, the cells can do their jobs—such as healing and growth—more efficiently. “Think of it as your morning coffee—red light therapy helps your cells wake up and get the job done!” says Dr. Kelley.

Red light therapy and other low-level light modalities take advantage of a phenomenon called photobiomodulation, which is how different components of our cells are activated or respond to different wavelengths of light, explains Erum Ilyas, M.D. a Pennsylvania-based board-certified dermatologist with Schweiger Dermatology.

To further explain the effectiveness, Dr. Ilyas says it’s helpful to compare how red light therapy works versus traditional skin devices, such as lasers and intense pulsed light (IPL).

Lasers cause controlled damage to the skin to trigger an inflammatory reaction to promote wrinkle reduction and reduced redness. Conversely, red light therapies don’t cause trauma to the skin, meaning positive effects are seen without the discomfort, healing time and possible reactive swelling of traditional lasers.

In other words, while red light therapy can penetrate the skin up to 6 millimeters beneath the surface, it doesn’t have to cause damage in order to boost cell activity, continues Dr. Ilyas.