7 Powerful Benefits of Sunshine and Red Light Therapy for Healing

For almost twenty years I was the medical director of a rehabilitation facility. People were often brought into the facility with pressure ulcers, venous ulcers, diabetic foot ulcers, or other chronic open wounds. We had a wound care team that would go around every day and change bandages on chronic wounds, which never saw light – and never healed. I worked hard to get the wound care nurses to use light, even buying the red lights for them to use, but it took too long. It was easier to just change a dressing.

What is Red Light Therapy?

In 1903 a Danish physician, Niels Ryberg Finsen, discovered that red light would improve the healing time of open wounds and sores. For this, he was awarded a Nobel prize. Much later, in space, the plants growing in the International Space Station (ISS) used red grow lights, and the astronauts noticed that their wounds healed faster when exposed to the light.[1] This is so simple, it’s amazing! Literally, light therapy is just exposing the wound to red light. We can now define light by its wavelength. The red light used in the space station has a wavelength of 630 nanometers.[2] That is barely into the red spectrum as you can see here:

These longer wavelengths of visible light penetrate into the body, turning on enzymes in the deep tissues. On the other hand, ultraviolet light releases all its energy on the surface of the skin, causing sunburns. Red light has multiple benefits for wound healing. For example, people with diabetes have blood flow and energy problems; the red light turns on the mitochondria to make ATP so the cells can do their work to heal. Moreover, the system for making nitric oxide causes the blood vessels to dilate, allowing more blood flow, more nutrients, and faster healing. The molecules that absorb the red light energy are called “Chromophores.”

What is a Chromophore?

This sounds like science fiction, but there are many substances in your body that are affected by light, these are called “chromophores.” Any molecule that absorbs light is a chromophore, such as the melanin that causes the skin to be tan, protecting you from sunburn. However, the ones However, we are interested in the mitochondria that increase ATP, nitric oxide, protein synthesis, and change calcium levels, all of which improve cell survival.[3]

These changes that happen from light are called “photobiomodulation” (PBM). The amount of light is important. More is not better. A low level of light stimulates these processes, but a high level of light causes inhibition. This is why some call it Low-Level Laser Therapy (LLLT) or cold laser. The most consistent effect of PBM on cells is a decrease in inflammation.[4]

What is red light good for?

There are many purported benefits of red light therapy, LLLT, PBM, or cold laser therapy:[5]

Dementia

Multiple small studies have been done shining red light through the skull and into the brain. One study using near infrared (just over 1,000 nm wavelengths) showed improvement in all parameters with just six minutes twice per day for eight weeks.[6] The improvement was much better than the drugs used for Alzheimer’s Disease.

Low Back Pain

A meta-analysis of multiple studies on back pain showed significant improvement in pain scores, but not in range-of-motion or functionality.[7]

Arthritis

Rheumatoid arthritis that is treated with LLLT shows improved pain scores in overall studies, but not range-of-motion or mobility.[8]

Tendinopathy

There are some reports that red light therapy can help tendinopathy such as “tennis elbow” or Achilles tendinopathy. It seems like the dose is important since the smaller wavelengths of red light only penetrate less than a millimeter into the tissue. Thus, infrared may be more beneficial.[9]

Hair loss

There are many studies that support the use of red light therapy for hair loss. It seems that it may work for male pattern hair loss in both males and females, but not alopecia areata.[10][11]

Aging skin and acne

There is a lot of talk about using red light to prevent aging. There are some studies, but they are very subjective and don’t often use controls so the results are not reliable. There is some evidence that it can increase the production of elastin and collagen, the building blocks of the skin. The same holds true for acne in the research is not conclusive.

Myopia

There are studies that may indicate mild slowing of the progression of childhood myopia (near-sightedness) with red light therapy.[12]

Weight loss

Using light to lose weight is like using paint to make music. It’s the wrong medium. Nevertheless, research is done,[13] which does not reach any statistical significance. People use the fact that there was an average of 1 kilogram lost to say that it works because they don’t understand research on weight. Everything works for weight loss, just not very well, or long term (except fasting, which always works! 😊) People are also told they can do body contouring, or body sculpting with red light. Red light therapy may help reduce the subcutaneous fat in the area that was treated, but the effect will likely be temporary and not due to any real weight loss.[14]

Notice that inflammation and wound healing are common with all of them. Some red lights that prevent and treat acne, and now specific LED red-light wands are available to treat herpes cold sores.

Those who sell the lights often overstate the benefits. There is reasonable evidence that it can improve wound healing, pressure sores, acne, and herpes, but there is little evidence for wrinkles and hair growth.[15] While red light stimulates the production of collagen in the skin, which heals wounds nicely, it may not induce hair growth or remove wrinkles. The researchers who performed a meta-analysis of studies say that it may not help, but it doesn’t hurt, so… why not?[16]

Can sunshine work instead of LED lights?

Think about it – photobiomodulation (PBM) has been around since the beginning of time. Sunshine has a full spectrum of visible light, some of which stimulate different chromophores. Some respond more to yellow light, others respond to blue light. There are certainly more benefits to a full spectrum of light than just one wavelength. Interestingly, the sun doesn’t give us high amounts of infrared or ultraviolet light. Most of the radiation from the sun is the light we see. The following illustrates the spectrum of sunlight reaching the earth:[17]

You can see that the intensity drops off rapidly in the ultraviolet (UV) spectrum, and a little more slowly in the infrared. We get more red and infrared radiation from the sun than ultraviolet.

Thus, a few minutes basking in the sunshine may have all the benefits as the red lights, and even heal wounds. The movie, The Other Side of Heaven, is a true story about a missionary in Tonga who slept with his feet uncovered. In the night, rats came and ate the soles of his feet, leaving open wounds. There were no doctors, so the locals used what they had. Rather than wrap the feet and wait for them to heal, they had him lay on the beach with the soles of his feet exposed to the sun to heal them. It worked! He was completely healed with no scars and no infections. However, later in life, he was diagnosed with skin cancer on the soles of his feet and his doctor was curious about how this could happen, so he explained the sun treatment to heal the wounds.

This illustrates several important points about sunshine.

1. Sunshine has ultraviolet light which stimulates immunity and kills microorganisms to prevent infection.
2. Sunshine has lots of infrared to induce healing.
3. Long exposure to sunlight can cause burns and non-melanoma skin cancers.

There is a great deal of argument over which wavelengths are the best for the skin. Those who manufacture lights attest that theirs is the best – the perfect wavelength. Others argue that theirs is better. The advantage of the sunshine is that it has all of them; none are left out.

Sunshine has several advantages over LED lights. It is a great disinfectant. Florence Nightengale designed hospitals to let in plenty of sunshine to help in healing wounds and preventing infections.[18] Much of the problem with wound healing is the growth of bacteria causing reactions and infections. Sunlight prevents this from occurring. The ultraviolet light that is often used to sterilize water also disinfects open wounds helping them to heal.[19]

Ultraviolet light is also an immune system modifier. It has been used for many years to treat skin issues such as:

• Psoriasis
• Eczema
• Jaundice
• Vitiligo
• Mycosis fungoides
• Morphea

But this is not all good. The ultraviolet light in sunshine can cause skin issues, such as sunburn, non-melanoma skin cancer, and activation of herpes.[20][21] Sunscreen seems to work well to prevent the outbreak of herpes[22] because it blocks UV light, but not infrared, so sunscreen can be used, but a better way is to limit the time in the sun. More is not better.

Fifteen minutes to healing

But light therapy does not need hours of exposure – only between ten and twenty minutes. If you spend fifteen minutes exposing your skin to the sun, you will get the benefits of any light therapy. If you want more red light and less UV, then do your sun-bathing in the morning and afternoon, avoiding the time between 11am and 2pm when the ultraviolet light is strongest. However, if you have an open wound you want to heal and disinfect, noon may be the perfect time to spend your fifteen minutes. Also, don’t do treatments every day; it is best to limit the sunshine to every other day. The missionary in Tonga might have healed just as fast with every other day sun treatments for fifteen minutes, and he probably would not have gotten skin cancer on his soles.

The Benefits of LED Lights

People who are sick, in a hospital or nursing home, or are otherwise not able to expose their skin to the sunshine have the advantage of many new LED light banks that can help them. Some find that sunlight stimulates herpes so they may want to have a light wand. The red light wands for herpes are put directly on the cold sore. Others want to avoid UV light so they can do sunshine in the early morning or late afternoon, or they can invest in a bank of red LED lights.

Some lights are easily affordable, while others are quite expensive. More expensive does not mean better, necessarily. It would be important to look at the quality of the light, wavelength, and the amount of light produced, as well as the size. It would not be useful to buy one larger than you need. Compare them and find the level you need. The wavelength does not seem to be essential. All red and infrared wavelengths have been shown to induce healing, the key is penetration. The longer the wavelength, the deeper the penetration. However, at a certain point the waves go right through the body and do not produce any effect. It seems that any lights between 640 nm to 700 nm in the visible light spectrum works well, as does near-infrared, 700 to 1,000 nm.

Light therapy is as old as life. What is new is the ability to deliver specific wavelengths of light to a specific spot. Sometimes that may be helpful. The wound care nurses in the nursing home didn’t have the time to spend with each patient, even just fifteen minutes every other day, and they didn’t have good results. Since the wounds were always covered, the patients were not able to go out in the sunshine, either. Even though the person who discovered this remarkable treatment won the Nobel Prize over a hundred years ago, it is still considered “investigational.” You can bet, that if there was a patent on red light, it would be accepted (and expensive!). You don’t need to wait for the data, nor do you need to spend hundreds or thousands of dollars on banks of red lights. The sunshine is free, and always available (unless you live in Forks, WA 😊)

 

 

 

 

 

 

 

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[1] https://www.liebertpub.com/doi/10.1089/104454703765035484

[2] https://ntrs.nasa.gov/api/citations/20160006558/downloads/20160006558.pdf

[3] https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

[4] https://pmc.ncbi.nlm.nih.gov/articles/PMC5523874/

[5] https://www.webmd.com/skin-problems-and-treatments/red-light-therapy

[6] Aging Dis. 2021 Jul 1;12(4):954–963. doi: 10.14336/AD.2021.0229

Transcranial Near Infrared Light Stimulations Improve Cognition in Patients with Dementia

Damir Nizamutdinov, et. Al.

[7] Arthritis Res Ther. 2015 Dec 15:17:360. doi: 10.1186/s13075-015-0882-0.

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[8] Brosseau L, Robinson V, Wells G, Debie R, Gam A, Harman K, Morin M, Shea B, Tugwell PLow level laser therapy (Classes I, II and III) for treating rheumatoid arthritis.Cochrane Database Syst Rev.(2005-Oct-19)

[9] Photomed Laser Surg. 2010 Feb;28(1):3-16. doi: 10.1089/pho.2008.2470. Low level laser treatment of tendinopathy: a systematic review with meta-analysis; Steve Tumilty, et. al

[10] Skin Appendage Disord. 2020 Sep;6(5):259-267. doi: 10.1159/000509001. Epub 2020 Jul 7.

Examining the Safety and Efficacy of Low-Level Laser Therapy for Male and Female Pattern Hair Loss: A Review of the Literature; Andjela Egger, et al.

[11] J Clin Aesthet Dermatol. 2021 Nov;14(11):E64-E75.

A Systematic Review and Meta-analysis of Randomized Controlled Trials of United States Food and Drug Administration-Approved, Home-use, Low-Level Light/Laser Therapy Devices for Pattern Hair Loss: Device Design and Technology; Suparuj Lueangarun, et al

[12] Tang J, Liao Y, Yan N, Dereje SB, Wang J, Luo Y, Wang Y, Zhou W, Wang X, Wang WEfficacy of Repeated Low-Level Red-Light Therapy for Slowing the Progression of Childhood Myopia: A Systematic Review and Meta-analysis.Am J Ophthalmol.(2023-Apr-07)

[13] Randomized Controlled Trial Lasers Med Sci. 2020 Apr;35(3):663-675. doi: 10.1007/s10103-019-02867-5. Epub 2019 Aug 31. Low-level laser therapy for weight reduction: a randomized pilot study, Ivana T Croghan, et al

[14] Randomized Controlled Trial Lasers Surg Med. 2009 Dec;41(10):799-809. doi: 10.1002/lsm.20855.

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[15] Lasers Surg Med. 2018 Jan 22;50(6):613-628. Light-emitting diodes in dermatology: A systematic review of randomized controlled trials; Jared Jagdeo 1 2 3, Evan Austin 1 2, Andrew Mamalis 3, Christopher Wong 2, Derek Ho 1 2, Daniel M Siegel 3

[16] Jared Jagdeo, Evan Austin, Andrew Mamalis, Christopher Wong, Derek Ho, Daniel M SiegelLight-emitting diodes in dermatology: A systematic review of randomized controlled trialsLasers Surg Med.(2018 Jan 22)

[17] https://www.researchgate.net/publication/360334322/figure/fig24/AS:1161622324293633@1653963752025/Solar-spectrum-at-Earths-surface.png

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