Questions about using light therapy to improve acne and breakouts? You’re not alone. Check out these frequently asked questions about acne and light therapy.
What is light therapy?
Light therapy (also known as LED therapy or phototherapy) is a simple, non-invasive treatment for acne. A light therapy device uses LEDs to shine specific wavelengths of light on the body and cells, resulting in a wide range of health benefits. Check out What Is Light Therapy for a full breakdown.
Do people use light therapy for acne?
Yes, light therapy is a popular acne treatment with dermatologists and estheticians. Light therapy is also widely used at home by the public to treat acne and breakouts. Blue light and red light are the most common wavelengths used to treat acne with light therapy.
Does light therapy really work for acne?
Yes! Light therapy is widely used by professionals and the public because it works and doesn’t come with a long list of side effects. Light therapy has been studied and tested in hundreds of clinical trials for skin and skin conditions. Research on acne and light therapy has shown that blue light, red light, and combination blue and red light therapy are effective treatments for acne and acne scarring.
How does light therapy work for acne?
Blue light therapy works for acne by killing the harmful bacteria that gathers on the skin and causes acne. Red light therapy works for acne by reducing inflammation, rejuvenating skin, and diminishing scarring on the skin. [1,2,3,4] Red light therapy helps heal skin and acne because the mitochondria in our skin cells absorb wavelengths of red light and use it to make cellular energy and reduce oxidative stress and inflammation. [5,6]
Clinical data shows that red light and blue light in tandem strongly downregulate lipid production in sebocytes, which are cells that produce sebum (skin oil). The results of trials suggest that roughly 415 nm blue light and 630 nm red light wavelengths, when used together, can have beneficial effects on acne by suppressing sebum production. 
What is an LED device?
LED stands for light emitting diode. LEDs in light therapy devices isolate specific wavelengths of light and shine them on the skin to heal and improve skin. LEDs are inexpensive, efficient, and long-lasting.
How often should I use light therapy for acne?
For best results, use an LED-based light therapy device for a few minutes every day or nearly every day. Consistency is key when it comes to light treatments and skin conditions. You’ll see much better results for acne if you use light therapy frequently.
Should you go to a dermatologist or do at-home light therapy for acne?
If you’re looking to treat acne symptoms with light therapy, you have a choice: pay for professional treatments from a dermatologist or esthetician, or buy an at-home treatment device you can use anytime.
The professional route is ultimately more expensive, though you get to speak with a skincare expert. The biggest advantage of at-home treatments is consistency. You can use them for a few minutes every day and see better results than if you went to a professional once or twice a week.
For more, check out this article on how often you should use light therapy.
What is blue light therapy for acne?
Blue light is probably the most common wavelength used to treat acne. Blue light is used against acne because it has an antimicrobial effect, killing bacteria on the skin that gathers in pores and oil glands to cause acne breakouts. [7,8]
In clinical research, blue light has been effective for acne treatment, inducing “photodynamic destruction” of bacteria on the skin.  Blue light can also help eliminate free radicals that oxidize on the face. You can buy numerous blue light therapy masks and wands online or from beauty retailers.
What is red light therapy for acne?
Red light is used to treat acne either on its own or in conjunction with blue light. Red light therapy isn’t antimicrobial like blue light. The mechanism of action for red light is that its wavelengths have an anti-inflammatory effect on the skin and promote the healing of skin and acne scars. [1,2,3]
While blue light kills acne-causing bacteria on the surface, red light works below the surface and in the cells, helping to repair damaged tissues and rejuvenate the skin from within.
Blue light or red light? What color light therapy should I use to treat acne?
Both! Blue light and red light can both have a beneficial effect on acne, but research is showing that light therapy may be most effective for acne when blue and red light work together. [3,4,10,11,12] Combination blue and red light therapy have reduced acne in clinical trials and shown a significant decrease in sebum production after LED treatments. [4,10]
Does near-infrared (NIR) light treat acne?
Research shows NIR light is less effective for acne treatment than red light therapy. . One trial compared red light with NIR light for acne and determined that red light therapy is “safe and effective to treat acne” compared to NIR treatments, which don’t work as well. 
Read more about the different colors and wavelengths used in light therapy in this article.
Does light therapy work for teens with acne?
Yes, and research is showing it’s more effective for treating teenage acne than chemical peels and other treatments.
A 2017 trial with teenagers compared light therapy acne spot treatments with salicylic acid peels. Using photographs to track the progress of the teenagers’ acne, researchers determined the light therapy treatments worked significantly better than the acid peels. Teens in the light therapy group showed significantly fewer new acne pustules after light therapy. 
The researchers concluded that combination blue and red light therapy is effective against acne due its anti-inflammatory and wound-healing properties. 
What are the side effects of light therapy?
Light therapy treatments for acne are well-tolerated and produce few side effects, especially compared to other acne treatments like peels and medications. [4,8,12] Clinical researchers studying light therapy and acne wrote that LED treatments are “safe and effective for treating not only inflammatory but also noninflammatory acne lesions.” 
In a wide range of clinical trials and populations, LED light therapy with red and blue wavelengths has proven safe and well-tolerated for people with acne, with virtually no side effects. [1,2,3,7,8]
Should I use light therapy for acne if I’m pregnant?
Consult a trusted healthcare provider first. Acne treatments involving light therapy or any other method can come with heightened risks for pregnant women.
Sources and References:
 Avci P, Gupta A, et al. Low-level laser (light) therapy (LLLT) in skin: stimulating, healing, restoring. Seminars in Cutaneous Medicine and Surgery. Mar 2013; 32(1): 41-52.
 Hamblin M. “Mechanisms and applications of the anti-inflammatory effects of photobiomodulation.” AIMS Biophys. 2017.
 Kwon HH, Lee JB, Yoon JY, Park SY, Ryu HH, Park BM, Kim YJ, Suh DH. The clinical and histological effect of home-use, combination blue-red LED phototherapy for mild-to-moderate acne vulgaris in Korean patients: a double-blind, randomized controlled trial. Br J Dermatol. 2013 May; 168(5): 1088-94.
 Jung YR, Kim SJ, Sohn KC, Lee Y, Seo YJ, Lee YH, Whang KU, Kim CD, Lee JH, Im M. Regulation of lipid production by light-emitting diodes in human sebocytes. Arch Dermatol Res. 2015 Apr; 307(3): 265-73.
 Karu T. Primary and Secondary Mechanisms of Action of Visible to Near-IR Radiation on Cells. Journal of Photochemistry Photobiology. 1999 Mar.
 Ferraresi C, Kaippert B, et al. Low-level Laser (Light) Therapy Increases Mitochondrial Membrane Potential and ATP Synthesis in C2C12 Myotubes with a Peak Response at 3-6 h. Photochemistry and Photobiology. 2015 Mar.
 Mayo Clinic. Acne Diagnosis and Treatment.
 Healthline. Is Light Therapy the Acne Treatment You’ve Been Looking For?
 Lee SY, You CE, Park MY. Blue and red light combination LED phototherapy for acne vulgaris in patients with skin phototype IV. Lasers Surg Med. 2007 Feb; 39(2): 180-8.
 Li WH, Fassih A, Binner C, Parsa R, Southall MD. Low-level red LED light inhibits hyperkeratinization and inflammation induced by unsaturated fatty acid in an in vitro model mimicking acne. Lasers Surg Med. 2018 Feb; 50(2): 158-165.
 Sadick NS. Handheld LED array device in the treatment of acne vulgaris. J Drugs Dermatol. 2008 Apr; 7(4): 347-50.
 Alba MN, Gerenutti M, Yoshida VM, Grotto D. Clinical comparison of salicylic acid peel and LED-Laser phototherapy for the treatment of Acne vulgaris in teenagers. J Cosmet Laser Ther. 2017 Feb; 19(1): 49-53.
 Aziz-Jalali MH, Tabaie SM, Djavid GE. Comparison of Red and Infrared Low-level Laser Therapy in the Treatment of Acne Vulgaris. Indian J Dermatol. 2012 Mar; 57(2): 128-30.