Healthier, smoother skin thanks to the use of red light therapy

Red light therapy is an innovative tool that many people are using to treat a variety of different skin concerns. Although it's a newer form of therapy, the use of red light therapy to improve skin health and quality has become very popular in traditional skincare, helping people achieve their skin health goals.

People use red light therapy on the skin for a variety of conditions, including:

• Promoting wound healing
• Reducing psoriasis symptoms
• Improving melasma
• Reducing post-inflammatory hyperpigmentation
• Reducing wrinkles and lines
• Improving skin strength and elasticity
• Improving acne
• Improving scars and stretch marks
• Reducing age spots

Although not strictly related to the skin, red light therapy is also used to stimulate hair growth on the head or face in people with areas of low hair density.

What is red light therapy?

Red light therapy is an innovative form of light therapy that has only recently gained mainstream acceptance. This form of therapy uses specific wavelengths of light in the red and infrared spectrum to stimulate biological changes in the body. These changes are believed to cause the skin improvements people experience with red light therapy.

Light therapy

Some scientifically minded people unfamiliar with light therapy may initially be skeptical of the concept of light therapies in general. The idea that simply shining a light on an area of the body can cause a biological effect may initially sound absurd; however, there are many good examples of light causing biological changes.

The most striking example of how light creates a biological effect is the process of photosynthesis, in which plant cells absorb light and capture its energy, combining carbon dioxide and water to produce oxygen and sugar.

Although humans don't use photosynthesis, there are many biological processes where it's well known and accepted that light influences the body. These include:

• Vitamin D Production - Exposure to specific wavelengths of ultraviolet light stimulates the production of vitamin D in skin cells. Vitamin D synthesized through stimulation from sunlight or other light sources containing ultraviolet light is considered more effective and efficient than taking vitamin D supplements or eating vitamin D-rich foods.
• Melanin production - Exposure to ultraviolet light stimulates the production of melanin, the molecule that gives skin a darker tone. Increased melanin production is what gives you a tan after time in the sun.
• Bilirubin Conjugation - Bilirubin is a chemical byproduct of blood cell breakdown. While in most people, the liver quickly breaks down bilirubin into other chemicals, a process called "conjugation," very young babies are sometimes unable to conjugate bilirubin, causing it to accumulate to toxic levels. Ultraviolet light can be used to conjugate bilirubin in these babies [1], preventing toxicity that can lead to brain damage.
• Vision - For most people, it can be easy to take vision for granted; however, the process of vision is a biological effect caused by light. Light-sensitive cells in the eye undergo a chemical change when exposed to light, causing not only conscious perception of light but also subconscious processes that regulate the sleep-wake cycle.

The idea that red light therapy creates a biological effect in the body is consistent with centuries of observations about how light has biological effects.

How does red light therapy work?

Red light therapy is believed to work by stimulating the mitochondria in your cells. Mitochondria are tiny organs in each of your cells; these subcellular organs are primarily known for being the component of the cell that produces all of the cell's energy. However, they also play an important role in reducing inflammation in the cell and regulating how long the cell lives.

Red light therapy actually uses wavelengths of red, visible light, and infrared, invisible wavelengths. The specific wavelengths used in red light therapy are believed to be absorbed by a molecule in the mitochondria called cytochrome C oxidase [2]. This molecule is part of the electron transport chain, a group of molecules that carry out a series of chemical reactions that result in the production of energy in the cell. Stimulating cytochrome C oxidase likely improves energy production in cells and may be the primary cause of the benefits of red light therapy.

The History of Red Light Therapy

Light therapy in general first gained the attention of medical scientists around 1895, when a Danish physician named Niels Ryberg Finsen began using light to treat infections [3]. Finsen went on to receive one of the first Nobel Prizes in Physiology or Medicine in 1903 for his work.

Research into red light therapy, however, began nearly a century later, when NASA scientists [4] were conducting research on the use of red light wavelengths to stimulate plant growth. While the experiment showed improved plant growth, an accidental discovery was that scientists who spent significant amounts of time exposed to red light experienced rapid healing of skin wounds they had sustained.

This discovery led to a separate line of research that uncovered multiple potential benefits for red light therapy. These potential benefits included not only improved skin health, but also improved sleep quality, decreased inflammation, and improved muscle recovery.

Effect of red light therapy on the skin

To fully understand how red light therapy can help improve the quality and health of your skin, it's essential to first understand the different ways this form of therapy is designed to actually affect your skin. By understanding what red light therapy can do to your skin and the biological effects it can have, you can better understand how red light therapy can help you achieve your skin health goals .

Collagen production

Collagen is a molecule that plays an essential role in skin health. Collagen is a connective molecule that helps skin cells adhere to each other and to other tissues, such as the fat cells beneath the skin. Collagen not only helps connect cells and tissues but also provides elasticity to the skin, allowing it to stretch and prevent damage.

Collagen is produced naturally in the body from nutrients found in the diet. The amount of collagen produced, however, begins to slowly decline for most people when they reach their mid-20s [5]. The decline in collagen production is quite gradual, decreasing only about 1% per year. This effect, however, worsens and causes lower collagen production that becomes more significant as we age.

When collagen production decreases, it ultimately leads to skin becoming less elastic and plump. This is the cause of the wrinkles that develop as we age and "sagging" skin. Low collagen levels also make skin more fragile as we age, making it more prone to damage whenever injuries occur.

Research shows [6] that red light therapy can stimulate cells called fibroblasts in your skin. These cells are responsible for collagen production, and using red light therapy can encourage increased collagen production. According to scientists at Harvard Medical School [7], the effect red light therapy has on fibroblasts and the levels of collagen they produce may help improve symptoms of aging.

Circulation

Blood circulation plays a crucial role in how well wounds and injuries heal. Blood not only carries the oxygen needed for cells to produce the energy they need to proliferate and heal, but also carries essential nutrients that serve as building blocks for new cells and tissues.

Good circulation also helps fight infection by bringing immune cells to the site of an injury and helping to remove waste and debris. This promotes healing but also reduces pain by reducing inflammation while stimulating healing at the site of the injury.

Red light therapy has been shown to promote the release of a chemical called nitric oxide where it is used. Nitric oxide helps dilate arteries where it is present, increasing blood flow to that specific area. It is believed that the effect red light therapy has on nitric oxide release is what causes red light therapy to improve circulation [8]. This improved circulation is one of the main benefits red light therapy can provide, likely playing a major role in many of its effects.

Cell proliferation

Cell proliferation refers to cells reproducing, leading to an increase in cell number. Cell proliferation is an important part of new tissue growth and healing. As cells multiply, the body forms new tissues and structures, repairing previously damaged tissue. The rate of cell proliferation is a key factor in what influences the rate of healing.

Red light therapy has been shown to promote cell proliferation [9], especially in cells under stress. This may lead to an improved rate of tissue healing and faster wound repair. The exact mechanism of red light therapy's cell proliferation is unknown, but it is likely a combination of mitochondrial stimulation and increased circulation.

Reduced inflammation

Inflammation is a normal part of the body's response to injury. Inflammation results in increased blood flow to an area and increased tissue permeability. These effects cause the area to become redder and warmer to the touch as increased blood flow results. Increased tissue permeability allows immune cells and nutrients to better reach the affected area, but it can also lead to some swelling at the site of the injury.

The inflammatory response plays an important role in healing. Improved blood flow and increased access of immune cells to the site help the area heal in the short term. A byproduct of inflammation is pain, which signals to your consciousness that there's a problem that needs to be addressed.

While inflammation is essential in the short term, it can be very detrimental if it becomes chronic. People with chronic inflammatory diseases, such as rheumatoid arthritis, will experience constant inflammation that causes discomfort and pain but doesn't actually result in the body repairing itself.

While inflammation can be caused by disease, it can also be caused by chronic or slow-healing injuries. Muscle injuries, infected wounds, or torn ligaments or tendons can all cause increased inflammation. This can actually hinder complete healing, as inflammation is a stage of healing that needs to stop before other stages can occur.

While chronic inflammation can inhibit healing, one of the most aggravating things it causes is pain. The swelling caused by inflammation can cause pain to develop and persist as long as the swelling and inflammation persist. Chronic inflammation often causes chronic pain that is very difficult to treat or control.

Research has shown that red light therapy's effect on mitochondria suppresses inflammation [10]. This may promote improved healing, allowing the body to progress beyond the early stages of inflammation and into more advanced healing. Suppressing inflammation also reduces pain, a benefit many people use red light therapy to achieve.

What skin conditions is red light therapy used to treat?

Red light therapy is a great option for many different types of skin problems, but it shouldn't be used for every type of skin condition. However, there are several skin conditions that people find red light therapy helpful in treating. Red light therapy shouldn't be used as an alternative to medical care prescribed by your doctor, but rather as a complementary therapy. You should always seek and follow your doctor's advice when treating skin conditions.

It's also important to seek medical advice when diagnosing a skin condition. There are many potential causes of skin problems, and only a qualified doctor can diagnose a skin condition or disease. It's important to never attempt to diagnose a skin condition yourself.

If you have a skin condition that red light therapy can likely help, or for which it seems to make sense, you don't need a prescription to begin therapy. However, it's a good idea to make sure your doctor knows you're using red light therapy.

Injuries

The initial discovery that red light therapy could have positive medical effects was in wounds. Using red light therapy to treat wounds is one of the oldest uses of this therapy and has been shown to improve wound healing speed [11]. Wounds usually heal on their own without treatment unless they are severe or infected, but they can heal more quickly with effective treatments.

Red light therapy is used to improve wound healing time, whether it's an external wound that breaks the skin or an internal wound that affects muscles or other tissues. Open wounds, however, are important to heal as quickly as possible, as healing prevents infections and other complications from developing. This not only ensures healing but also helps reduce the risk of scarring, reinjury, or other complications.

Psoriasis

Psoriasis is a skin disease in which the immune system is believed to trigger excessive skin cell proliferation. Psoriasis causes scaly, itchy patches of skin. This can lead to discomfort and skin irritation that is difficult to eliminate. A concern many people with psoriasis have is its cosmetic effect, as it can cause visible and unsightly rashes. The ability to conceal these rashes depends primarily on the areas affected by psoriasis.

There are several potential treatments for psoriasis, though none are a complete cure. One of the most commonly used treatments that has been shown to help people with psoriasis is light therapy using ultraviolet light. The wavelengths of this high-energy light therapy reduce skin cell overgrowth and improve psoriasis symptoms in the treated areas.

Red light therapy can be used by people with psoriasis, but it's more likely to improve symptoms of pain and skin irritation than to actually improve the skin lesions themselves. The inflammation and irritation they cause, however, can be reduced with red light therapy.

One potential benefit of using red light therapy for psoriasis may be that it helps protect the skin from UV light damage [12]. UV light used to treat psoriasis may increase the risk of skin cancer eventually developing, and red light therapy may provide a protective effect. The extent to which red light therapy actually provides protection, however, is still a subject of ongoing research.

Melasma

Melasma, also called chloasma or the "mask of pregnancy," is a common skin condition that causes dark patches to develop on the skin. While pregnancy can increase the risk of developing melasma, it can also develop in non-pregnant women or men.

Melasma usually occurs on the face and is more common in women or people with darker skin. Hormones, sun exposure, stress, and thyroid disease are considered risk factors for developing melasma. While melasma can disappear on its own, especially if related to pregnancy or hormone-based medications, it can also be permanent and often returns if it disappears on its own.

People with melasma often use red light therapy to improve skin quality and reduce the hyperpigmentation it causes. Studies suggest that red light therapy inhibits an enzyme called tyrosinase [13] that produces melanin, the pigment that causes melasma patches to develop. Using red light therapy helps even out skin tone and may provide cosmetic improvements for those with melasma.

Post-Inflammatory Hyperpigmentation

Post-inflammatory hyperpigmentation, also called hypermelanosis, occurs when the body produces excess melanin in the skin after inflammation has occurred. In this condition, inflammation causes skin cells to increase melanin production, leading to darker skin in the previously inflamed areas.

Although post-inflammatory hyperpigmentation fades on its own, this process can take several years or longer. Because post-inflammatory hyperpigmentation leads to discoloration that can be cosmetically undesirable, many people who develop this condition prefer to try methods like red light therapy to speed up the process.

As with people with melasma, red light therapy is used by those with post-inflammatory hyperpigmentation for its effect on evening out skin tone and reducing dark spots caused by excess melanin production. By suppressing melanin production, red light therapy can improve discoloration caused by post-inflammatory hyperpigmentation.

Acne

Acne is a skin condition that causes hair follicles to become clogged, leading to blocked pores. This leads to the development of blackheads and whiteheads, which can become infected or cause scarring. Acne commonly affects the face, creating a noticeable cosmetic defect that can be very undesirable.

Bacterial infections can cause acne; however, the blackheads and whiteheads associated with acne can also be linked to many other causes. Light therapy has been studied to treat acne, with both ultraviolet and red light therapy being helpful [14]. Ultraviolet light is believed to provide its benefit by helping destroy bacteria that may be clogging the pore, while red light therapy improves healing and reduces the risk of long-term scarring.

Scars

Scars develop when an injury fails to heal in a way that returns the skin or affected area to its original appearance. Scars can develop after injuries, but they can also be a concern after surgery or when stretch marks develop. Scars are usually a long-term problem that can be permanent if left untreated.

Red light therapy may help reduce the likelihood of scarring [15] developing after an injury or may reduce the severity of existing scars. Decreasing inflammation and improving circulation, two effects commonly associated with red light therapy, will help injuries heal properly. This reduces the likelihood of scar tissue developing due to impaired healing and increases the chances of full and complete healing.

Several effects associated with red light therapy also help existing scars heal partially or completely. Increased collagen production can help damaged skin tissue regain its elasticity. This can be especially helpful for stretch-related scars, such as stretch marks after pregnancy. Increased circulation and an even skin tone can help scarred areas heal better, making the skin more even and helping it appear more consistent with its pre-injury appearance.

Age-related changes

As we age, our skin undergoes several changes. Some of these changes are cosmetic, primarily altering the appearance of your skin. Others are more structural, affecting how your skin functions. Often, structural changes will lead to cosmetic changes, as they affect the skin's normal function and increase the risk of damage.

Age-related skin changes have two main causes. First, there are normal changes that occur with aging. In skin, decreased collagen production is the main cause of these changes, but circulation and hormonal changes can also play a role. Second, damage accumulates over time. Whether from sun exposure, tobacco use, or even injury, the more time the skin has to accumulate damage, the more changes it will experience.

In addition to age-related changes, as we get older, we tend to take more and more medications. Many medications can affect skin quality and cause skin damage. While not specifically age-related, the likelihood of this occurring increases as we get older.

There are three main age-related changes that many people commonly experience as they get older. They include:

• Age spots - Also called liver spots, age spots become more common with age. These spots are also more common in people with greater sun exposure throughout their lives. Age spots appear as flat brown, black, or tan patches on the skin.
• Wrinkles - Because collagen is less abundant, the skin has less elasticity. This makes the skin less able to maintain its shape and leads to the appearance of wrinkles. Wrinkles begin to develop in areas of the skin that are commonly wrinkled, but eventually spread.
• Fragility - As skin loses its elasticity and ability to hold its shape, it becomes more fragile. Decreased connectivity between skin cells and other cells makes it easier for the skin to tear or separate from other layers of tissue.

Red light therapy is used to reduce age-related changes in the skin by stimulating collagen production and evening out skin tone. Helping skin tone become more even by inhibiting excess melanin production will help age spots fade. Increased collagen production helps skin become more robust and wrinkle-free.

More research on red light therapy for skin health

In addition to the research we've already discussed specific to different skin conditions, there is a much larger body of research supporting the benefits of using red light therapy to promote skin health and well-being.

Studies on red light therapy for skin

Skin-related studies exploring red light therapy can be in vivo, performed on humans, but are also often in vitro , performed in a laboratory setting on cells taken from humans or animals. Skin cells are particularly well-suited for in vitro studies, providing greater insight into the biological effects that are actually occurring.

In vitro studies

In 2015, researchers conducted an in vitro study [16] exposing cultured human cells to red LED lights. The results, published in the International Journal of Photoenergy , showed that exposure to 660 nm red light increased the rate at which skin cells multiplied and helped improve their migration.

An article from the Journal of Wound Management and Research [17] published in 2018 also tested the effects of light on cultured skin cells. The researchers found that red light or red light combined with infrared light “could modulate fibroblast proliferation and collagen synthesis.” They also determined that the combination of red light and infrared light produced better results than red light alone.

In 2019, the Journal of the American Academy of Dermatology published research [18] that found that treating skin cells with red and low-level infrared LED lights “significantly increases the gene expression of hyaluronic acid synthase (HAS2) and elastin (ELN).” These genes are related to the production of hyaluronic acid and elastin, two molecules that play an important role in keeping your skin hydrated, supple, and elastic and that decline as we age. The researchers found that these effects occurred in just three days. The researchers noted: “Because red and low-level infrared light stimulated the production of several biomarkers associated with anti-aging skin benefits, these findings suggest that red and low-level infrared light treatments present opportunities for daily at-home treatments for patients with photoaging and photodamaged skin.”

Another study [19] was also published in 2019, examining the effects of red light therapy on skin healing. Published in PLOS One , this study used in vitro porcine (pig) skin that researchers damaged and then examined its recovery when exposed to light. The researchers found that using red light for at least 10 minutes accelerated the recovery of the samples, while blue and purple light did not.

In 2021, a study [20] published in the International Journal of Cosmetic Science found that using red or infrared light to treat cultured human skin cells increased the expression of four different genes associated with skin health, increased collagen production, increased elastin production, and improved protein connectivity in the skin. The study also found increased production of ATP, the molecule used by cells for energy, when red and infrared light were combined.

A very interesting study [21] published in Frontiers in Oncology in 2022 showed that red light used on melanoma cells, cells of a certain type of skin cancer, "prevented tumor growth and increased the expression of immune markers." These results are very early and do not mean that red light therapy should be used to treat skin cancer; however, they indicate that future research into this possibility is needed.

A 2023 study [22] published in Lasers in Medical Science studied human skin cell cultures exposed to 661 nm (red) light. The study showed that the skin cell cultures not only healed faster when exposed to this light, but that the healing was in part due to an effect that resulted in the cells orienting themselves more effectively and moving to the areas where they were needed.

In vivo studies

A 2014 study [23] published in the Journal of Clinical and Experimental Dermatology Research followed 29 patients who underwent broadband infrared therapy once a month for five months. After these treatments, 76% of the test subjects reported that they were satisfied to very satisfied with the treatments. The results measured included degrees of wrinkles in the tested area, wrinkles at the corners of the eyes, and cheek skin laxity, with more than three-quarters of the test subjects noticing changes in each of these measures.

A very important study [24] was published in 2020 in the Journal of Biophotonics . This study examined the safety profiles of red light therapy, testing its effects on a diverse group of 155 people. The study noted specific differences in how safe red light therapy was in people with differences in skin pigmentation. Specifically, they found that red light therapy was “safe up to 320 J/cm2 for skin of color and 480 J/cm2 for non-Hispanic Caucasian individuals.” This finding indicates that those with darker skin pigmentation may absorb more red light and be more susceptible to dose-related complications from red light therapy.

A 2020 controlled study [25] published in BMJ Open examined the effects of using high-intensity red light to treat chronic wounds. The study included 60 people and found that the therapeutic effects of using the treatment on chronic, poorly healing wounds “are significant and far superior to those of conventional dressings.”

Red Light Therapy for Skin Reviews

In addition to many independent studies demonstrating the benefits of red light therapy for skin health, there are several important reviews. These reviews bring together data from numerous studies, helping to better contextualize the research conducted and its implications. Reviews also play an important role in suggesting potential new research avenues, protocols, and ways to strengthen existing research.

Some recent important reviews on the state of red light therapy research related specifically to skin health include:

• A 2013 review [26] published in Seminars in Cutaneous Medicine and Surgery found that red light therapy “appears to have a wide range of applications in dermatology, especially in indications where stimulation of healing, reduction of inflammation, reduction of cell death, and skin rejuvenation are needed.” The review also noted that it could reduce damage caused by ultraviolet light, both by preventing it and by treating it afterward. This review occurred before the widespread use of red light therapy in dermatology and likely played a role in its widespread adoption.
• A 2015 review [27] published in the Biomedical and Pharmacology Journal analyzed the different methods of administering red light therapy, as well as different potential explanations for how red light therapy actually works. The study helped clarify how red light therapy impacted healing and noted that more research was needed to determine the parameters that should be used to administer red light therapy.
• A 2016 review [28] published in Wound Healing . This study reviewed red light therapy protocols and noted an increase in the clinical use of red light therapy to treat wounds and ulcers. The study also reviewed how experiments have confirmed the potential beneficial effects of red light therapy for wound healing.
• A 2018 review [29] published in Lasers in Medical Science . The review noted that red light therapy “represents the emerging and safest tool for the treatment of many conditions, such as inflammatory skin conditions, aging, and hair growth disorders.” The review also noted that red light therapy “has now entered common practice among dermatologists,” but recommended that more controlled studies be conducted to better establish its effectiveness.
• Another 2018 review [30] published in Medical Research Archives found that the volume of research on red light therapy for skin care had doubled in the previous eight years. The review explored several previously studied benefits of red light therapy, including its use in treating skin wounds, erosive mucositis in oncology, leg ulcers, burns, radiodermatitis, acne, and hypertrophic scars. It also noted that red light therapy reduces inflammation after other skin treatments that can cause inflammation. The review also identified several new potential applications in which red light therapy was showing promise. These areas included alopecia, cellulite, and other skin conditions.
• A 2021 review [31] published in the Aesthetic Surgery Journal concluded that “there is a reasonable body of evidence from clinical trials to support the role of low-energy red/near-infrared light as a safe and effective method of skin rejuvenation, treatment of acne vulgaris and alopecia, and especially body contouring.” The review also suggested potential methods to improve future studies, such as improving methodologies and the number of patients included in each study.

How is red light therapy used?

Using red light therapy to improve skin health is relatively simple. Before you begin, however, there are a few steps you should take:

1. Make sure you don't have any contraindications . Not everyone should use red light therapy, and you should make sure there are no reasons why you shouldn't use it. If you're unsure, consult your doctor before using it.
2. Learn about red light therapy. There can be significant differences in the quality of different red light sources, and there's more to it than just having one red light source. Make sure you understand the quality of the products you'll be using.
3. Make sure you have access to red light therapy . The changes red light therapy provides are worthwhile, but they tend to be more gradual. To use red light therapy correctly, you'll need regular access to a red light therapy panel or device.

When you're ready to start using red light therapy, performing the treatment will be quite easy.

1. Turn on the red light source.
2. Be sure to wear protective eyewear.
3. Make sure the area to be treated is uncovered.
4. Position yourself about 30 to 40 centimeters from the source.
5. Allow the light source to irradiate the area to be treated for 10 to 20 minutes.
6. Repeat regularly, three to seven times a week.

If the manufacturers of the red light panel or your doctor provide different instructions regarding the length of time, distance, frequency, or other factors, you should follow their advice.

TheraFactor Red Light

At TheraFactor, we offer a wide variety of red light therapy products designed to deliver specific wavelengths of light thought to help improve skin cell function and, therefore, improve overall skin health. Our panels are designed to deliver the maximum amount of the right light to the largest possible area.

Customer feedback on their skin has been excellent. Check out some before-and-after photos of red light therapy and our growing repository of glowing reviews .

DISCLAIMER : TheraFactor devices are not clinically proven to diagnose, treat, cure, or prevent any medical condition. TheraFactor devices are Class II general wellness devices intended to affect the body through topical heating and support of cellular function. The scientific studies referenced in this article are for informational purposes only.

References:

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