Blue Light Therapy: Uses, Benefits, and Side Effects

Blue Light Therapy: Uses, Benefits, and Side Effects


Blue light therapy is one area of light therapy that is quickly gaining recognition for some of its amazing benefits and especially when used in conjunction with red and NIR light therapy.

In this article, we’ll explore the uses, treatment benefits, and side effects of blue light therapy. 

We hope this will help educate some of the benefits of blue light treatment when used alongside proven and highly effective red light treatment.

The Benefits of Blue Light Therapy

All wavelengths of light have specific effects on the body. In this section, we discuss some of the many potential advantages of blue light treatment. 

Blue light is widely used to treat a variety of skin conditions. And, some of these can be treated at home.



Repair Sun Damage and Treat Precancerous Lesions and Skin Cancer

Blue light treatment really shines when it comes to help treating skin cancer and actinic keratoses, or precancerous lesions caused by sun damage. Treating an individual actinic keratosis lesion is effective, and the treatment only targets diseased tissue with minimal effect on surrounding tissue.

Some in vitro studies suggest that blue light therapy may have anti-cancer properties since it causes damage and destruction of B16F10 melanoma skin cancer cells. In this study, B16F10 melanoma cells were treated with 470 nm light from a light-emitting diode (LED) device. The treatment inhibited cell growth. The number of B16 melanoma colonies that formed after treatment was smaller than in non-treated samples.

Skin cancer treatment using blue light is called photodynamic light therapy or PDT. This in-clinic treatment involves applying a topical photosensitizing drug on skin with sun damage. This topical drug is applied to an actinic keratosis lesion. This is followed by exposure to blue light. This non-invasive procedure kills skin cancer and precancerous lesions that have absorbed the light and the photosensitizing medication. 

Several treatment sessions are often needed to completely remove actinic keratosis.



Blue Light Therapy Treatment for Mild to Moderate Acne

Blue light therapy has come to the forefront in skin care as an effective treatment of mild to moderate acne. These wavelengths effectively kill acne-causing bacteria on the skin’s surface. Interestingly, Propionibacterium acnes (acne-causing bacteria) emits a photosensitizer which makes it exceptionally sensitive to light and vulnerable to damage by specific wavelengths.

Blue light treatments work best on acne when combined with red and near infrared (NIR) therapy. This is because red and near infrared light can absorb deeper all the way through each layer of skin and even into the underlying tissues. There, red and NIR treatment can address any systemic inflammation.

This is important because inflammation causes chemical changes in the skin that make the skin a hospitable environment for P. acnes. Therefore, addressing the underlying inflammation can be a way to ensure healthy skin that doesn’t put out a welcome sign for P. acnes, potentially reducing the incidence of future acne outbreaks.



Blue Light Therapy for Anti-Aging and Skin Wounds

An animal study on skin wounds revealed that treatment using 470nm blue light stimulated the release of nitric oxide (NO), a vasodilator, which helps bring blood (and therefore oxygen, immune system substances, and nutrients) to a wound. Blue light significantly decreased the size of the wound after a week of treatment.

A review of several studies compared the efficacy of LED vs. laser treatment for skin wounds. One of the notable conclusions from this review was that blue light “can achieve significant effects in cells.” In particular, hemoglobin and melanin show exceptional absorption of wavelengths shorter than 600nm: this suggests that blue light can support oxygen transport in the body (hemoglobin in the blood carries oxygen throughout the body). 

Blue light therapy can also have positive impacts on anti-aging, although it is typically used for surface level treatments, whereas red light therapy is more often used for anti-aging purpses. 



Blue Light Therapy and Chronic Inflammatory Skin Conditions

Ultraviolet therapy is a common light therapy treatment for mild to moderate chronic skin disorders. However, because of its side effects, researchers are looking into safer skin care alternatives. One paper reviewed the results from a number of effects of blue light therapy on hyperproliferative chronic inflammatory skin diseases, including atopic dermatitis, psoriasis, and eczema.

This paper’s authors found that blue light therapy has a similar stimulating effect on cellular mitochondria as red and NIR light. Blue and red/NIR light promote greater production of adenosine triphosphate, or ATP. That’s the primary cellular fuel in humans. Since the wavelengths are very short, however, this effect is limited to the epidermis. 

This is why red/NIR treatment, along with blue light therapy can be the key to reducing systemic inflammation that causes or contributes to chronic skin diseases.



How Blue Light Therapy Treats Rosacea

A study on combining blue and red light treatments showed remarkable outcomes in two patients with rosacea. Conventional treatment for rosacea includes tetracycline, which can have long-term side effects. Photodynamic therapy combined red and blue light with methyl ester aminolevulinate. 

The first patient received ten sessions of 480nm blue and 650nm red light for 15 minutes at each wavelength, following a variety of other treatments that had been unsuccessful. The second patient received the same sequential blue and red light treatment along with topical azelaic acid; this also followed a series of unsuccessful treatments. Both patients experienced a reduction in erythema (burning) and itching after the LED treatments.

The study’s authors concluded that these case reports show the efficacy and safety of blue and red LED therapy for patients with rosacea.



Atopic Dermatitis (Eczema)

Blue light therapy has also been used successfully to reduce severe itching associated with mild to moderate atopic dermatitis. Study participants received five daily treatment sessions over a 6-month period. Researchers observed a 29% reduction in disease severity 15 days after treatment; 41% after 3 months; and 54% improvement after 6 months.

How Blue Light Therapy Treats Psoriasis

A paper published by the American Academy of Dermatology Association stated that at-home blue light treatments were effective in treating psoriasis. The paper referred to two studies. 

The first study involved daily treatment for four weeks:

  • Patients experienced continuous reduction in the size of the treated area
  • Patients experienced reduced redness and scale in the treated area
  • No patients experienced skin damage from the treatment; the only side effect was a temporary darkening of the skin, which cleared up on its own after the treatment period. 



The second study had different timing. For the first four weeks, patients were instructed to treat their psoriasis patches once a day, 5-7 times a week. For the following eight weeks, patients were instructed to reduce treatments to once a day 3 times a week. Some also applied psoriasis medication (synthetic vitamin D) to the affected area.

In the second study, two patients had their psoriasis clear up completely in the treated area. Most patients saw a reduction in the size of the treated psoriasis patch. Two patients had complete clearing of the treated psoriasis patch. 



Other Uses for Blue Light

Aside from skin care, blue light can have several important benefits for your well being.

Regulate Your Circadian Rhythm

These very short, high-energy wavelengths don’t absorb into the skin beyond 0.07 to 1mm. They are, however, easily absorbed by our light-sensitive retinas, which is the key to one of the most important functions of blue light: helping to regulate your circadian rhythm.

Humans are programmed to feel a burst of energy in the morning. All colors of the rainbow affect the sleep-wake cycle, but none more so than blue light. When blue light interacts with photoreceptors in the eyes, it sends a signal to “wake up,” increasing alertness as well as mental sharpness.

At night, though, excessive exposure to blue light can interfere with sleep. Blue light suppresses the release of melatonin, which makes us feel sleepy.



You can blame ultra-sensitive photoreceptors in your eyes. These are called melanopsin retinal ganglion cells, and they have a direct link to the brain’s master clock. These receptors are extremely sensitive to blue wavelengths. 

Americans spend an average of 7 hours a day on electronic devices. Blue light is emitted by TVs, smartphones, tablets, gaming systems, computer monitors, along with white LED and fluorescent fixtures. Since there is no shut-off time from electronics that would give our bodies a cue that it's bedtime, many of us suffer from sleep disturbances.

The takeaway is that blue light is wonderfully energizing during the day and especially when used in conjunction with red and NIR light therapy.



Sharpen Mental Abilities

Blue light therapy stimulates wakefulness, alertness, and sharp mental abilities including learning and memory retrieval. This is especially handy during the "post lunch dip" in energy, according to researchers.

Relieve Depression and Seasonal Affective Disorder

Bright light (full-spectrum natural sunlight) therapy has been used to treat Seasonal Affective Disorder and depression not related to lack of sunlight. A big component of the success of this treatment is believed to be energizing/stimulating/mood boosting blue light. 

Blue light therapy is a mood-booster according to researchers who observed 25 participants with SAD and/or general depression with seasonal intensification. The study participants saw a 51% increase in mood scores after treatment.

A 2020 animal study revealed that blue light deprivation induced depression in gerbils, suggesting that a daily dose of sunshine is important for mental health.



Treat Jaundice in Newborns

Bright "bili lights" with blue wavelengths are used to treat newborns with jaundice. The treatment breaks down bilirubin (the substance that makes skin and eyes appear yellow), allowing the body to expel the bilirubin naturally and restore normal skin appearance.

Another study found that when jaundiced newborns were exposed to blue light, the treatment prevented atopic dermatitis and other allergic skin disorders for the first five years of life.

Is Blue Light Therapy Effective?

Blue wavelengths have been shown to be effective in treating many chronic skin disorders, as well as psychological disorders including depression and SAD.

Phototherapy is a treatment that should be used consistently for the best results. You may need ongoing treatments for acne, psoriasis, other chronic inflammatory skin disorders, as well as depression/SAD. 

However, photodynamic therapy is a significantly different type of treatment. This cancer treatment is done in-clinic since photodynamic therapy (unlike phototherapy) involves the use of topical photosynthesizing drugs along with light to create a stronger reaction and effectively destroy actinic keratoses. You may need several treatments to get rid of actinic keratoses, along with annual maintenance sessions.

Emerging research suggests that blue light therapy could potentially offer therapeutic effects to treat premenstrual depression.  

How Blue Light Therapy Works

Light acts on the body via two distinct pathways: the eyes and the skin. Blue wavelengths are too short to absorb into the skin beyond the epidermis. Therefore most of the effects occur through the eyes.

In a way, humans are remarkably similar to plants in that we draw energy directly from the sun, specifically electromagnetic radiation we call light. Researchers have found that light influences alertness, hormone secretion, heart rate, sleep/wakefulness, body temperature, and even gene expression.

Whether it's absorbed through the eyes or the skin, we are photosensitive creatures, and we can use light to our advantage.

Various studies have confirmed that treatment with blue wavelengths can stimulate cellular energy production, reduce inflammation, and kill bacteria and cancer cells.  

The first two effects (increased cellular metabolism and reduced inflammation) are shared with red and NIR light therapy. The therapeutic applications of red/NIR light therapy are farther-reaching simply because of the significantly deeper absorption into the body.



Blue Light Therapy Side Effects

Before the industrial age and the advent of artificial light, we got just as much blue light as we needed with daily sun exposure. However, the biological impact of light is just now being studied intensely. This research has helped us understand the power and side effects of phototherapy by isolating the effects of each wavelength.

When it comes to treatment, blue wavelengths on their own (without adding photosensitizing drugs) are considered safe and have very few risks as long as you opt for short treatment sessions, wear eye protection, and use a quality LED therapy panel.



Potential Risks and Complications of Blue Light Therapy 

Blue light treatment should be avoided if you have a condition called porphyria. This rare disorder of the blood results in heightened light sensitivity. People with allergies to porphyrins and people with lupus should also not use blue light therapy. Photodynamic therapy is always doctor-prescribed and administered.

We recommend limiting blue light therapy treatments to daylight hours in keeping with the body’s natural rhythms, and avoid blue light therapy after sunset unless you wear light-blocking goggles.

Blue Light Therapy At Home

Blue light therapy is beneficial in small doses and is considered a safer therapeutic option for skin care than UV light therapy or bright light therapy.

For the best results, you'll need a high quality LED therapy device that emits blue, red, and NIR wavelengths. This device should have strong light energy output to ensure maximum absorption.

Harness the many varied benefits of blue light including skin health, mental sharpness, and energy by taking your treatment early in the day. Charge your “batteries” with energizing blue light! instead of starting the day stressed out and in a rush. A soothing blue and red light therapy session is a great way to jump-start your well being first thing in the morning.

Learn more about how red and NIR light therapy works as well as some of its most common applications: skin health, joint health, and much more.