The general public often sees red light therapy as of light therapy (aka phototherapy). While more research is needed on its efficacy, it has shown promise in anti-aging benefits. I will engage with a sesh of red light on occasion, but as someone who struggles with acne, I'm Team Blue Light Therapy. Blue light is quite literally a killer of acne, and a lesser-known fact is that it's also an effective treatment against precursors to skin cancer—and it's got dermatologists and studies to back it up. Consider this your crash course on all things blue light therapy, including the best skincare devices and tools that the dermatologists think are worth your money. Let's get after it, shall we?
What are the benefits of blue light therapy?
Blue light therapy has been shown to improve acne and help prevent breakouts before they happen. It is also a highly effective treatment for destroying skin cancer cells in tandem with photosensitizing drugs, explains board-certified dermatologist Ellen Marmur, MD. Pretty cool, amiright? Let's break down how these two skin conditions can benefit from blue light:
Acne: Blue light directly affects and kills the bacteria (i.e., Cutibacterium acnes) that are responsible for producing acne. It also "targets cells that (over)produce sebum or oil and decreases inflammation," says board-certified dermatologist Sara Hogan MD.Precancerous skin conditions: In combination with photosynthesizing drugs—i.e., drugs that are applied on precancerous areas and are activated by light—blue light is a highly successful treatment against pre-skin cancer spots. Formed from long-term UV exposure, these spots are called actinic keratoses and have the potential to turn into squamous cell cancers.However, the benefits don't stop there. In fact, dermatologists love blue light therapy for psoriasis, eczema, and other chronic skin conditions, explains Dr. Hogan.
How does blue light therapy work?
Controlled use of blue light at specific wavelengths works by targeting different types of cells to treat a range of skincare problems. "Blue light acts on different cellular targets in the skin to induce therapeutic benefits, including the improvement of acne, chronic inflammatory skin conditions, sun damage, and wound healing," says Dr. Hogan.
Acne treatment with blue light works by targeting and destroying Cutibacterium acnes bacteria. This type of bacteria lives on our skin, and when it gets trapped under our hair follicles and pores, it can cause inflammation and irritation that may lead to breakouts. "With consistent use, blue light therapy will clear your breakouts and mitigate your acne," says Dr. Marmur. FYI, she says at-home treatments combining blue light with topical formulations containing photosomes—i.e., light-activated skincare—will improve the benefits.
In the case of skin cancer treatment, dermatologists use a process called photodynamic therapy (PDT). Photosynthesizing drugs are applied to the affected face and/or scalp, and blue light is added—the light essentially works to "activate" the drugs, and a chemical reaction is created, killing the cancer-causing cells.
Is blue light therapy different from blue light from electronic devices and UV light?
This is where it gets a little complicated, but know this: Medical blue light therapy is different from both UV light and the blue light emitted by electronic devices. Let's get into the ~science~:
Blue light is part of the visible light spectrum, which is what the human eye can see, explains Dr. Hogan. The visible light spectrum ranges from wavelengths of ~400 to 700 nm, and UV light has shorter wavelengths of between 100 to 400 nm. At these shorter wavelengths, ultraviolet radiation occurs—this is where harmful UVA and UVB rays are present resulting in premature aging, sunburn, and increased risk of skin cancer.
On the other hand, medical blue light therapy and blue light emitted from electronic devices fall within the same wavelength, but, but! blue light therapy is controlled and used at higher intensities to target specific skin conditions. Electronic blue light is much less intense, and though it may cause eye issues and sleep disruption, it's just an inadvertent result of screen use. Got it? Okay, cool.
Are there any negatives of blue light therapy?
While the use of blue light devices at home is an incredibly great acne treatment, Dr. Marmur notes that different types of acne may need to be treated in conjunction with topicals, oral medication, and other methods. She says one treatment is also unlikely to suffice, noting that you will need several treatments per breakout, as well as consistent use to see long-term benefits in the appearance of your acne. And if it wasn't obvious, you'll 100% need to go to a board-certified dermatologist about any pre-cancer concerns to determine what the best course of action is and to see if photodynamic therapy is the right treatment for you.
A lesser-known fact is that blue light can increase hyperpigmentation, particularly among individuals with darker skin tones, says Dr. Hogan. "Patients with melasma may want to use blue light settings in LED masks with caution." While there are slim risks associated with blue light devices, we need more controlled, random studies to establish clear guidelines for doctors and also to provide standards for companies creating at-home devices. This leads us to...
What's the best blue light therapy device?
Dr. Marmur stresses the fact that when choosing your at-home LED therapy device, it's important to make sure "that your options are FDA-cleared or approved and backed by science." FWIW, legit devices that are FDA-approved can be pretty steep in price, but it's a one-time investment, and real people, including myself, have seen serious benefits.
