Is Red Light Therapy Perfect for Hyperpigmentation Reduction?
Hyperpigmentation is a condition in which patches of skin become darker than the surrounding areas. Red light therapy is the use of low-energy visible and infrared light to trigger healthy responses.
The scientifically proven benefits of red light therapy for hyperpigmentation include:
- reduction of patch size
- complete elimination of some dark patches
- decrease in the color intensity of remaining patches
- SPF-15 sunscreen level of UV protection
- collagen production without wounds (as compared to microdermabrasion and chemical peels)
- tighter skin from new collagen
- reduced sagging from new elastin
- reduced blood vessel overgrowth
- reduced inflammation
- reduced redness
- increased blood flow to nourish tissue health
What is Hyperpigmentation?
Hyperpigmentation is a chronic condition caused by the overproduction of melanin in UV-exposed areas[i], hormone imbalances, or inflammation. Melanin is the pigment that gives color to the skin. Hyperpigmentation is the uneven distribution of melanin.
The three most common types of hyperpigmentation are:
- melasma caused by hormone imbalances
- sunspots caused by ultraviolet light exposure
- post-inflammatory hyperpigmentation caused by inflammation
Psychological Effects of Hyperpigmentation
In a study of the effects of post-inflammatory hyperpigmentation, men and women said they felt embarrassed by their discoloration problems[ii].
About a third of the subjects said they would take advantage of psychological support for the social problems they attributed to their skin issues. Over 80% of the women in the study said that they covered their pigmentation areas with makeup.
Hyperpigmentation Causes and Symptoms
Hyperpigmentation is caused by sun exposure, hormone imbalance, or an inflammatory reaction.
Sun Spots
Sun spots, also known as liver spots, age spots, and solar lentigines, are brown, tan, or black spots that appear on the skin as a result of overexposure to the sun.
The small spots appear on the face, hands, and other areas of the body that are frequently exposed to the sun.
Sunspots are more common in people over the age of 50. Age spots are typically seen in older adults or those who have spent prolonged periods in the sun.
Melasma
Melasma, also referred to as chloasma or “the mask of pregnancy,” is characterized by large patches of darkened skin. Melasma causes brown or grayish-brown patches of skin that are often symmetrical and have irregular borders.
Melasma discoloration often appears on the forehead, face, and stomach and is more common in women, especially those who are pregnant or taking birth control pills. The underlying cause is hormonal changes.
People with medium to darker skin tones are also more susceptible to developing melasma.
Post-inflammatory Hyperpigmentation
Post-inflammatory hyperpigmentation (PIH) is the appearance of darkened spots or patches on the skin after an inflammatory skin condition such as acne or eczema. These spots can occur anywhere on the body.
PIH occurs after the skin has been injured or inflamed, such as from acne, eczema, or a cut. The affected skin may be darker than the surrounding skin and can take months to fade.
You can learn all about using red light therapy for post-inflammatory hyperpigmentation in my article 5 Common Causes of Post-Inflammatory Hyperpigmentation (PIH).
Hyperpigmentation Treatment Options
Hyperpigmentation treatment options include:
- red light therapy
- chemical peels
- laser/light treatments
- mesotherapy
- microneedling
- systemic therapy
Introduction to Red Light Therapy for Hyperpigmentation Reduction
Red light therapy is the low-energy delivery of visible and infrared light to create healthy changes. You can get red light therapy at spas and salons, or buy a device for at-home use.
The color light you use depends on how the condition responds. Hyperpigmentation responds well to yellow, red, and infrared light.
We call it “red light therapy,” but really any visible color and invisible infrared all fall under the “red light therapy” umbrella.
Red light therapy has been tested scientifically since it was discovered in 1967. Over 9,000 papers on its use demonstrate that it is safe, effective, and the absolute minimum of side effects.
A NASA study in the year 2000 determined that LEDs were as effective as lasers at producing healthy results. That drove the priced down, and created a market for red light therapy at home.
Although it’s not yet a standard treatment for hyperpigmentation, red light therapy has good scientific evidence for its use. You will learn more about the science supporting red light therapy use for hyperpigmentation below in this article.
Red light therapy is a cosmetic procedure. It can be performed by a skincare professional, but devices are available for at-home use.
You can use a laser for red light therapy, but it is a different configuration than a regular laser. A normal laser is very high-powered. When used in red light therapy, the laser is much weaker.
Laser therapy is the high-energy delivery of light, whereas red light therapy is the low-energy delivery of light. This is why light emitting diodes (LEDs) are ideal for red light therapy, as they are naturally low-energy light delivery systems.
Red light therapy one side effect when it comes to hyperpigmentation. It can actually create pigmentation in some people. This is why you should get a device that allows you to turn off infrared. This side effect only happens with infrared light, and therefore you should use yellow and red light if this happens to you.
Chemical Peels for Hyperpigmentation
A chemical peel is a cosmetic treatment that involves applying a chemical solution to the skin to exfoliate the outer layers and promote new skin cell growth. The peeling process removes the discolored skin, reducing the appearance of hyperpigmentation and improving overall skin texture and tone.
Chemical peels can vary in intensity, depending on the depth of the peel and the type of chemical used. Mild peels affect only the outermost layer of skin. Stronger peels penetrate more deeply into the skin.
Chemical peels can cause temporary redness, peeling, or discomfort, but they are generally safe and effective for treating hyperpigmentation.
Laser Therapy for Hyperpigmentation
Laser therapy for hyperpigmentation is a medical treatment that uses a high-intensity laser beam to target and break up excess pigmentation in the skin.
The laser energy causes the pigment to fragment. The immune system then eliminates the remains. the hyperpigmentation, and the treatment is typically performed by a trained medical professional. Laser therapy for hyperpigmentation is considered safe and effective.
Side effects include redness and discomfort. Multiple treatments may be necessary to achieve optimal results.
Mesotherapy for Hyperpigmentation
Mesotherapy is a medical technique that involves injecting small amounts of medication, vitamins, and other substances into the skin[iii].
Substances injected to reduce hyperpigmentation include vitamin C, glutathione, and tranexamic acid (TA)[iv]. Only the TA has significant science to back its use. The TA injection prevents the skin from making pigment[v].
Results are often good after several treatments, but often do not last. Mesotherapy is typically performed by a trained medical professional using a fine needle, and it is generally considered a safe and minimally invasive procedure.
Microneedling for Hyperpigmentation
Microneedling involves using a small handheld device with tiny needles to create controlled micro-injuries on the skin’s surface. The process is designed to stimulate the body’s natural healing response. The immune system responds to the micro damage by producing collagen and elastin. These improve the skin surface and structure.
To address pigmentation, the Dermafrac technique involves adding skin lightening agents to the needles[vi].
Microneedling is considered a minimally invasive procedure and is performed bay medical or a cosmetic professional.
Systemic Therapy for Hyperpigmentation
Systemic therapy approaches hyperpigmentation with internal medications. It is used for deep or widespread hyperpigmentation issues.
Oral tranexamic acid (TA) is the internal version of the topical TA injected via microneedling. It reduces the production of melanin responsible for pigmentation.
Oral isotretinoin reduces the activity of pigment-producing cells.
The treatment is typically prescribed and monitored by a dermatologist or other medical professional.
Systemic therapy for hyperpigmentation may cause side effects and requires close monitoring.
What the Science Says About Red Light Therapy for Hyperpigmentation
Red light therapy has been studied on people and in the Petri dish for reducing and removing hyperpigmentation. This therapy can literally eliminate hyperpigmentation, and it does it with no side effects or downtime.
Red light therapy has multiple benefits that happen alongside the hyperpigmentation reduction. While you’re doing hyperpigmentation reduction, the light is also giving you skin tightening, reduced sagging, and rejuvenation.
The scientifically proven benefits of red light therapy for hyperpigmentation include:
- reduction of patch size
- complete elimination of some dark patches
- decrease in the color intensity of remaining patches
- SPF-15 sunscreen level of UV protection
- collagen production without wounds (as compared to microdermabrasion and chemical peels)
- tighter skin from new collagen
- reduced sagging from new elastin
- reduced blood vessel overgrowth
- reduced inflammation
- reduced redness
- increased blood flow to nourish tissue health
| Scientific Studies Using Red Light Therapy to Reduce Hyperpigmentation | |||
|---|---|---|---|
| Date | Wavelength | Treatment | Results |
| 2018 | 633 nm red and 830 nm infrared | Skin types V or VI treated with red or infrared 36 times over 9 months | significant improvements reducing size and number of spots |
| 2018 | 940 nm infrared | Microdermabrasion followed by infrared light, once a week for 8 weeks | significant reduction in melasma color and size |
| 2008 | pulsed 660 nm red | Healthy and polymorphous light eruption thighs treated with red light therapy before UV exposure | 85% of subjects achieved 50% ore more reduction in UV damage; therapy acted similarly to SPF-15 sunscreen |
Red and Infrared Light Both Successful at Reducing Melasma
A 2018 study tested 633 nm red and 830 nm infrared light therapy on 60 women with melasma and skin types of V or VI[vii]. The National Institutes of Health advises that the Fitzpatrick Classification of Skin Types[viii] V and VI are defined as:
- Skin Type V: ” Brown skin. Never burns. Tans very easily.”
- Skin Type VI: ” Black skin. Heavily pigmented. Never burns, tans very easily.”
The women received red light therapy with red or with infrared light 36 times over 9 months.
Both subjective and objective measurements showed that the treatments resulted in significant improvements in the melasma pigmentation. Both red and infrared light were effective at reducing the size and number of dark spots.
Infrared Red Light Therapy Reduces Hyperpigmentation
A 2018 study tested 940 nm infrared light on seven women with melasma on the face[ix]. All 7 had failed to get results using other melasma therapies.
Treatment was on one side of the face, with the untreated side acting as the control.
The treated side received microdermabrasion and then 940 nm infrared light therapy. The subjects received weekly treatments for eight weeks.
To test the effects, the researchers used white light photographs, ultraviolet light photographs, Melanin Index scores, and Melasma Area and Severity Index scores.
At the 12th week after starting, researchers used these tools to assess progress. On both subjective and objective measures, the microdermabrasion combined with the red light therapy significantly reduced pigmentation.
660 nm Red Light Therapy Acts as SPF-16 Sun Block in 13 Subjects
A 2008 study tested pulsed 660 nm red light on creating cellular resistance to ultraviolet redness and freckles.
Two of the 15 patients had polymorphous light eruption (PLE), and 13 were classified as healthy.
First the researchers tested ultraviolet light on the thigh to determine the amount of UV it took to produce redness and freckles.
Then, the subjects received 5, 6, or 10 treatments with 660 nm red light on an untested part of the thigh. This was the “pre-treatment” that acted as the sunscreen protection.
The researchers than shone ultraviolet light on the UV-only and the pre-treated red light therapy targets.
The red light therapy pre-treated side produced a 50% reduction in ultraviolet induced redness in 85% of the subjects. The subjects with PLE had equal results to the healthy subjects. The red light therapy had the same protective benefits as SPF-15 sunscreen.
One subject had post-inflammatory hyperpigmentation at the start, which significantly reduced in size and darkness after red light therapy.
Science of How Red Light Therapy Reduces Hyperpigmentation
Have you ever heard of tyrosine or tyrosinase? If you have any type of hyperpigmentation, these two biochemicals are probably involved.
Tyrosine is one of the twenty building blocks of proteins, meaning that it is an amino acid.
Tyrosinase is a biomolecule that speeds up chemical reactions, which means that it is an enzyme.
The chemical reaction that tyrosinase speeds up is the conversion of tyrosine into melanin. This is key to how red light therapy reduces hyperpigmentation.
Red light therapy suppresses the enzyme tyrosinase, and that prevents tyrosine from converting into the melanin pigment.
Nitty Gritty Science of Red Light Therapy for Hyperpigmentation
If you wanted that statistics for nerds, here are four studies demonstrating the mechanisms that reduce pigmentation.
Below are the biomolecules involved, and then a table showing how red light therapy affected each one.
Melanin (Pigment)
Melanin is a pigment that is responsible for the color of the skin. It is produced by melanocyte cells. Melanin is made up of different types of molecules, including the amino acid tyrosine and its derivatives.
Melanin also plays a protective role in the skin. It helps to absorb and scatter harmful ultraviolet (UV) radiation from the sun.
Microphthalmia-Associated Transcription Factor (MITF) (Protein)
Microphthalmia-associated transcription factor (MITF) is a protein that plays a key role in the development and function of the cells that produce the melanin pigment in the skin.
Tyrosinase Related Protein 1 (TRP-1) (Enzyme)
Tyrosinase-related protein 1 (TRP-1) is an enzyme involved in the production of melanin, the pigment that gives color to our skin, hair, and eyes. TRP-1 is closely related to the enzyme tyrosinase.
Tyrosinase (TYR) (Enzyme)
Tyrosinase (TYR) is an enzyme involved in the production of melanin pigment. TYR converts tyrosine into an intermediate form before it gets turned into melanin.
Microtubule-Associated Protein Light Chain 3 (LC3) (Protein)
Microtubule-associated protein light chain 3 (LC3) is a protein that plays an important role in the process of autophagy, which is a cellular mechanism for degrading and recycling damaged or unnecessary proteins, organelles, and other cellular components. LC3 is used as a marker for autophagy.
p62 (Protein)
p62 protein is a protein that plays an important role in autophagy (cellular cleanup), apoptosis (cellular suicide), and signaling pathways. p62 acts as a receptor for selective autophagy, a process by which specific intracellular components such as damaged organelles or protein aggregates are targeted for degradation by autophagy.
Human Microvascular Endothelial Cells (HMEC) (Cell)
Human microvascular endothelial cells (HMEC-1) are a type of endothelial cell that line the walls of small blood vessels called microvessels. They are commonly used in research studies as a model system for studying angiogenesis (new blood vessel formation from existing vessels), inflammation, and vascular biology.
Vascular Endothelial Growth Factor (VEGF) (Protein)
Vascular endothelial growth factor (VEGF) is a signaling protein that plays an important role in the formation of blood vessels, a process called angiogenesis. VEGF stimulates the growth and proliferation of endothelial cells, which form the inner lining of blood vessels.
VEGF has been shown to play stimulate the growth and survival of melanocytes, the cells that produce the pigment melanin. VEGF can also regulate the expression of various genes involved in melanin synthesis.
Stem Cell Factor (SCF) (Protein)
Stem cell factor (SCF) is a protein that plays a key role in the development and maintenance melanocyte stem cells. SCF stimulates the production of melanin.
Melanosome (Organelle)
A melanosome is an organelle found in specialized pigment-producing cells called melanocytes. Melanosomes are responsible for the production, storage, and transport of the pigment melanin, which gives color to the skin.
Within melanosomes, the amino acid tyrosine is converted into melanin through a series of enzymatic reactions catalyzed by enzymes such as tyrosinase and tyrosinase-related protein 1 (TRP-1).
B16F10 (Cell)
B16F10 cells are a type of mouse melanoma cell that are derived from melanoma tumors.
| Biological Target of Yellow (Amber), Red, and Infrared Light on Hyperpigmentation | ||||
|---|---|---|---|---|
| Light-emitting diodes at 830 and 850 nm inhibit melanin synthesis in vitro | 590 nm LED Irradiation Improved Erythema through Inhibiting Angiogenesis of Human Microvascular Endothelial Cells and Ameliorated Pigmentation in Melasma | Light-emitting diode 585nm photomodulation inhibiting melanin synthesis and inducing autophagy in human melanocytes | Inhibitory effect of 660-nm LED on melanin synthesis in in vitro and in vivo | |
| Biological Target | 2012[x] 830 & 850 nm (infrared) | 2022[xi] 590 nm (yellow) | 2018[xii] 585 nm (yellow) | 2016[xiii] 660 nm (red) |
| tyrosinase-related protein (TRP-1) | decreased TRP-1 activity | decreased TRP-1 activity | ||
| tyrosinase (TYR) | decreased TYR expression | decreased TYR expression | decreased TYR expression | |
| microphthalmia-asociated transcription factor (MITF)) | decreased MITF expression | decreased MITF expression | decreased MITF expression | |
| microtubule-associated protein light chain 3 (LC3) | increased autophagy of LC3 | |||
| p62 protein | degraded p62 protein | degraded p62 protein | ||
| autophagy-inhibited 3-Methyladenine (3-MA) | melanin returned when 3-MA added | |||
| human microvascular endothelial cells (HMEC-1) | reduced migration and tube formation of HMEC-1 | no effect on viability or apoptosis of HMEC | ||
| toxicity | none | |||
| vascular endothelial growth factor (VEGF) | decreased secretion/expression of VEGF | |||
| stem cell factor (SCF) (pro melanogenic) | decreased secretion/expression of SCF | |||
| insulin-like growth factor 1 (IGF-1) | inhibiting AKT/PI3K/mTOR signaling pathway with IGF-1 reversed inhibitory effect of wavelength on migration and tube formation | |||
| pilot study | facial erythema and pigmentation in melasma patients | |||
| melanosome | inhibited melanosome maturation | |||
| melanin | decreased melanin content | |||
| microtubule-associated protein light chain 3 (LC3) | autophagic punctate structures and degradation of LC3-I to LC3-II | |||
| p62 protein | p62 protein degraded | |||
| 3-Methyladenine (3-MA) | reversed effects,
inhibited type III Phosphatidylinositol 3-kinases (PI-3K); inhibited autophagy; blocked autophagosome formation |
|||
| B16F10 cells | decreased ERK activity | |||
| depigmenting effects of 660-nm LED result from downregulation of MITF and tyrosinase expression due to increased ERK activity | ||||
| HRM-2 mice | downregulation of tyrosinase and MITF reduced UVB-induced melanogenesis | |||
[i] Piętowska Z, Nowicka D, Szepietowski JC. Understanding Melasma-How Can Pharmacology and Cosmetology Procedures and Prevention Help to Achieve Optimal Treatment Results? A Narrative Review. Int J Environ Res Public Health. 2022 Sep 24;19(19):12084. doi: 10.3390/ijerph191912084. PMID: 36231404; PMCID: PMC9564742.[ii] França K, Keri J. Psychosocial impact of acne and postinflammatory hyperpigmentation. An Bras Dermatol. 2017 Jul-Aug;92(4):505-509. doi: 10.1590/abd1806-4841.20175645. PMID: 28954099; PMCID: PMC5595597.
[iii] Mammucari M, Maggiori E, Russo D, Giorgio C, Ronconi G, Ferrara PE, Canzona F, Antonaci L, Violo B, Vellucci R, Mediati DR, Migliore A, Massafra U, Bifarini B, Gori F, di Carlo M, Brauneis S, Paolucci T, Rocchi P, Cuguttu A, Di Marzo R, Bomprezzi A, Santini S, Giardini M, Catizzone AR, Troili F, Dorato D, Gallo A, Guglielmo C, Natoli S. Mesotherapy: From Historical Notes to Scientific Evidence and Future Prospects. ScientificWorldJournal. 2020 May 1;2020:3542848. doi: 10.1155/2020/3542848. PMID: 32577099; PMCID: PMC7305548.
[iv] Piętowska Z, Nowicka D, Szepietowski JC. Understanding Melasma-How Can Pharmacology and Cosmetology Procedures and Prevention Help to Achieve Optimal Treatment Results? A Narrative Review. Int J Environ Res Public Health. 2022 Sep 24;19(19):12084. doi: 10.3390/ijerph191912084. PMID: 36231404; PMCID: PMC9564742.
[v] Liu Y, Han Y, Zhu T, Wu X, Yu W, Zhu J, Shang Y, Lin X, Zhao T. Targeting delivery and minimizing epidermal diffusion of tranexamic acid by hyaluronic acid-coated liposome nanogels for topical hyperpigmentation treatment. Drug Deliv. 2021 Dec;28(1):2100-2107. doi: 10.1080/10717544.2021.1983081. PMID: 34596008; PMCID: PMC8491700.
[vi] Singh A, Yadav S. Microneedling: Advances and widening horizons. Indian Dermatol Online J. 2016 Jul-Aug;7(4):244-54. doi: 10.4103/2229-5178.185468. PMID: 27559496; PMCID: PMC4976400.
[vii] Mpofana N, Abrahamse H. The Management of Melasma on Skin Types V and VI Using Light Emitting Diode Treatment. Photomed Laser Surg. 2018 Oct;36(10):522-529. doi: 10.1089/pho.2018.4486. Epub 2018 Sep 18. PMID: 30227084.
[viii] Cutaneous Melanoma: Etiology and Therapy [Internet], Retrieved April 17, 2023; https://www.ncbi.nlm.nih.gov/books/NBK481857/table/chapter6.t1/
[ix] Barolet D. Dual Effect of Photobiomodulation on Melasma: Downregulation of Hyperpigmentation and Enhanced Solar Resistance-A Pilot Study. J Clin Aesthet Dermatol. 2018 Apr;11(4):28-34. Epub 2018 Apr 1. PMID: 29657669; PMCID: PMC5891084.
[x] Kim JM, Kim NH, Tian YS, Lee AY. Light-emitting diodes at 830 and 850 nm inhibit melanin synthesis in vitro. Acta Derm Venereol. 2012 Nov;92(6):675-80. doi: 10.2340/00015555-1319. PMID: 22334261.
[xi] Dai X, Jin S, Xuan Y, Yang Y, Lu X, Wang C, Chen L, Xiang L, Zhang C. 590 nm LED Irradiation Improved Erythema through Inhibiting Angiogenesis of Human Microvascular Endothelial Cells and Ameliorated Pigmentation in Melasma. Cells. 2022 Dec 7;11(24):3949. doi: 10.3390/cells11243949. PMID: 36552713; PMCID: PMC9776419.
[xii] Chen L, Xu Z, Jiang M, Zhang C, Wang X, Xiang L. Light-emitting diode 585nm photomodulation inhibiting melanin synthesis and inducing autophagy in human melanocytes. J Dermatol Sci. 2018 Jan;89(1):11-18. doi: 10.1016/j.jdermsci.2017.10.001. Epub 2017 Oct 11. PMID: 29065997.
[xiii] Oh CT, Kwon TR, Choi EJ, Kim SR, Seok J, Mun SK, Yoo KH, Choi YS, Choi SY, Kim BJ. Inhibitory effect of 660-nm LED on melanin synthesis in in vitro and in vivo. Photodermatol Photoimmunol Photomed. 2017 Jan;33(1):49-57. doi: 10.1111/phpp.12276. Epub 2016 Nov 3. PMID: 27696509.
