From NASA to Bathroom Selfies: What Is LED Light Therapy?

A quick history lesson: light-emitting diodes were originally developed by NASA at the end of the 20th century to help plants grow in space. Later on, it was noticed that certain LED wavelengths helped promote faster healing of skin lesions in scientists who worked under these lights.

This has sparked an interest in how LEDs might affect human health further — and eventually, what started as a high-tech space experiment has since evolved into a glowing trend beloved by beauty gurus.

As an ex-doctor and a certified health fad hater, looking at posts of influencers showing off their shiny LED masks has definitely left me wondering: is it just another unsubstantiated wellness trend, or is LED light therapy here to stay? Let’s see what current scientific evidence says.

What is LED light therapy?

Light-emitting diode therapy, or LED therapy, is a type of pain-free, non-invasive treatment that uses light to penetrate the skin in order to help manage various health concerns.

There’s a chance you might’ve already heard of red or blue light therapy (commonly referred to as RLT or BLT), which have been trending on social media for quite a while now. RLT and BLT are two common types of LED light therapy.

Below, we discuss their differences, as well as briefly cover what other types are out there.

Key types of light in LED light therapy

LED light therapy uses different wavelengths that correspond to various colors, which can penetrate into different depths of the skin and tissues deeper within the body. We know this might sound a bit like rocket science, but bear with us.

Since each color has a distinct ability to reach the structures within different depths of the body, all of them are associated with different potential health effects.

For example, blue light is known to affect only the uppermost layer of the body, which has led scientists to explore its effects on the human skin (more on that later), whereas red and near-infrared light has the ability to penetrate deeper and, therefore, potentially have an effect on what’s deeper within, like joints.

Unlike sunlight, LED light is not associated with sun damage or skin cancer. Below, we review the potential benefits of some of the different LED light colors.

Red light

Red LED light therapy is the most thoroughly researched of all. RLT exposes cells and tissues to low-level light — in particular, red and near-infrared light (NIR light). While you can see red light with the naked eye, NIR light is outside the visible light spectrum and invisible to humans.

In comparison to other types of light, these two ‘colors’ are able to penetrate the deepest into the body. By doing that, they may trigger certain biological processes in your body, potentially leading to what we observe as health effects.

Emerging evidence suggests that RLT may be helpful in addressing:

• Skin concerns, including signs of aging and dark spots
• Hair loss due to male/female pattern baldness
• Joint and muscle pain

Scientists are also looking into whether RLT could aid in accelerating the wound healing process, have the potential to improve muscle recovery after exercise, as well as if it may have a use in helping manage depression, cold sores caused by herpes simplex virus, or even addressing neurodegenerative disorders, such as Alzheimer’s disease.

However, though we know the most about how this type of light may affect the human body when compared to others, many uncertainties remain. More on that later.

Blue light

Blue LED light is known to affect the uppermost layer of the skin. However, it doesn’t mean that it shows less promise than the other types of LED light — research has suggested that BLT may be an effective method to help manage certain skin conditions, such as acne and psoriasis.

BLT is particularly popular for acne management since it has the potential to help kill acne-causing bacteria, P. acnes. Healthcare providers may choose to treat acne with devices that combine red and blue light.

Orange light

Orange light, sometimes referred to as amber light, has the potential to penetrate the depth of the skin that’s somewhere in between where blue and red light can reach.

Research about the health effects of orange light is still ongoing, and currently available studies are rather limited. Interestingly, one study has shown promise in orange light helping alleviate period cramps.

Currently, scientists are looking into whether it could be useful for helping reduce the appearance of melasma, a skin condition that causes patches of dark skin on areas of the face exposed to the sun.

In conclusion, more studies are needed to understand the potential uses of orange light.

Green light

Green LED light has the ability to penetrate slightly deeper than blue does but does not reach the depths of the skin that yellow light can.

Similarly to orange light, green light has not been explored very widely by scientists, at least yet. Limited evidence suggests that it may show promise in aiding with wound healing and promoting pain relief, as well as helping with body contouring.

Hopefully, we’ll get to know more about these types of light and what their potential health effects and uses could be in the near future.

Considering LED light therapy? Here’s what to know

First things first, while LED light therapy is considered to be generally safe for most, and the risk of side effects seems to be minimal, purchasing and using any kind of LED light device at home without consulting your healthcare provider beforehand isn’t the best idea.

If you have any complaints about your health, including a skin issue that might seem benign to you, see a medical professional first. They’ll be able to make a proper diagnosis, make a treatment plan, and tell you if LED light therapy might be a potentially effective and safe adjunct option for you as part of the plan.

If they recommend LED light therapy, you may choose whether you want to do it by using an at-home device or if you’d like to undergo in-clinic treatments:

• In-clinic LED light treatments are applied by doctors or estheticians, depending on your concern. They may use LED light together with other treatments. It’s important to note that professional devices may be more powerful and customizable than those you can purchase for at-home use.
• Over-the-counter LED devices — such as masks, wands, or panels — may be used alone or following a professional treatment, which helps maintain treatment consistency at the convenience of your own home. However, with so many options available on the market, we don’t know for sure how their effectiveness compares to those applied in clinical studies and used by professionals at clinics.

If you’re considering purchasing an at-home device, ask your healthcare provider for an individually tailored regimen. Also, make sure to read the instructions of your specific device carefully, use the device as instructed by the manufacturer, avoid direct eye exposure, and always wear goggles for eye protection while using the device.

LED light therapy: safety considerations

Certain groups of people are recommended to refrain from LED therapy as there’s insufficient evidence about their safety or a higher risk of side effects.

This includes pregnant and lactating individuals, people with cancer, and those with skin conditions that make you more sensitive to light (such as rosacea, a skin disease that causes excess skin redness), or those using certain medications that may cause increased sensitivity to light. Ask your healthcare provider whether any drugs you’re using may put you at a higher risk of photosensitivity.

There’s much we still don’t know about LED light therapy, including its long-term safety. More research is needed.

LED light therapy: the takeaway

Emerging evidence suggests that LED light therapy does show promise for a range of health and aesthetic concerns, with red and blue being the types of light most thoroughly studied and widely used.

However, while it’s thought to be generally safe in the short term, as with any other type of treatment, it's not one-size-fits-all. If you have any complaints you think LED light therapy may be helpful with, consult your healthcare provider for a proper diagnosis first. They’ll let you know if LED light therapy could be a safe and appropriate choice for you.