If you have acne, you’ve likely heard of blue light therapy before — it’s been used in dermatologists’ offices for years to help eliminate acne-causing bacteria at its source. And for a while, expensive at-home devices have utilized the same technology to provide similar advantages for a fraction of the price. But now, with some devices costing less than $40, blue light therapy at home has truly become accessible.

So, aside from serving as a trendy and futuristic addition to your next self-care Sunday (and resulting in some strange selfies), how do the at-home blue light for acne devices on the market actually work to give you a clear complexion? Here, it’s all explained by two dermatologists.

Why Blue Light for Acne?

Blue light is a range of light (wavelength of 415 nanometers, to be precise) that’s scientifically proven to be effective in eradicating acne at the source and healing the skin from within, states Marnie Nussbaum, M.D., a dermatologist based in New York City. How? “Blue light has been demonstrated to penetrate the skin’s hair follicles and pores, which harbor bacteria and can lead to inflammation and consequently acne. Bacteria are highly receptive to the blue light spectrum — it hinders their metabolism and eradicates them,” she explains. Unlike topical treatments, such as some of the most effective spot treatments for acne, which work to reduce inflammation and bacteria on the surface of the skin, light therapy eliminates the acne-causing bacteria (also known as P. acnes) within the skin— before it can feed off the oil glands and cause that redness and inflammation, adds Dr. Nussbaum.

Benefits of Adding In Red Light

If you’re wondering why some visible light devices (referred to as “visible light” because you can see the colors) appear to emit more of a purple glow, that’s because some options on the market actually utilize a combination of red and blue light. “Red light has conventionally been used for anti-aging purposes because it helps stimulate collagen production. At the same time, it aids in reducing inflammation, which is why it is beneficial alongside blue light in treating acne,” explains Joshua Zeichner, M.D., the director of cosmetic and clinical research in dermatology at Mount Sinai Hospital in New York City.

Best Uses for Blue Light Therapy Devices

Experts concur that at-home blue light treatments are most effective for mild to moderate acne — not severe cystic or scarring acne. These devices are also not effective against blackheads, whiteheads, acne cysts, or nodules, according to the American Academy of Dermatology.

Read: They are most suitable for your conventional crimson, non-cowardly blemishes, given that they are not considerably profound or distressing, as stated by Dr. Zeichner. Moreover, even though employing illumination to the dermis might appear severe, it is actually milder than customary superficial commodities. (Simply abstain if you possess a dermatological ailment such as rosacea, cautions Dr. Nussbaum.)

While medical findings demonstrate that at-home devices can be equally effective in addressing mild acne, they provide a lower level of intensity compared to what can be achieved in a medical setting, according to Dr. Zeichner. However, this also means that they can be used more frequently (most devices recommend daily usage) — and due to their compact and affordable nature, they are more convenient to incorporate into one’s routine. Additionally, a typical treatment in a dermatologist’s office can cost anywhere from $50 to $100 per session, and patients are typically advised to come in twice a week for several months, making it a costly commitment, adds Dr. Zeichner.

Options for At-Home Blue Light Acne Devices

The FDA has approved several at-home LED devices that emit visible light (blue, red, and blue-red light) for the treatment of mild to moderate acne. Some popular options? Tria Beauty’s Positively Clear 3-Step Skincare Solution (Purchase It, $149, amazon.com) is a compact option that works well for accessing hard-to-reach areas of the face and does not require cartridge replacements. Another option is the Me Clear Anti-Blemish Device (Purchase It, $30, amazon.com) which utilizes a combination of blue light, sonic vibration, and “gentle warming.” Other choices include the DRx SpotLite (Purchase It, $52, drdennisgross.com) from the well-regarded skin-care brand Dr. Dennis Gross that has received approval from celebrities. The LightStim (Purchase It, $169, dermstore.com) is another red and blue light device that not only reduces inflammation and destroys acne-causing bacteria but also claims to enhance circulation, collagen, and elastin production.

While the duration of time you’ll have to use each device differs (so follow the instructions for proper use to ensure you actually gain the benefits of fighting acne!), the time investment for most at-home devices ranges from approximately six to 20 minutes daily to observe results, depending on the number of facial sections you wish to treat. So, while it certainly adds a time-consuming step to your skincare routine, it’s definitely far less time than you spend in bed scrolling through Instagram on a daily basis, not to mention probably gentler than other at-home beauty treatments you may undergo regularly, such as a bikini wax.

How to Select Your Device

Always search for an FDA-approved light device that was tested and approved for proper use, states Dr. Nussbaum, who recommends the Tria device since it’s more potent than other at-home blue light treatments. That being said (similarly to when purchasing any acne cleanser), the price of the product doesn’t necessarily correspond with effectiveness, adds Dr. Zeichner. “Without direct comparisons between different light therapy products to determine their effectiveness, we simply do not know which ones work better,” he explains.

How to Integrate Blue Light Therapy Into Your Current Skincare Routine

While the Tria system comes with a cleanser and spot treatment that work together with the device (the spot treatment contains niacinamide and black tea instead of salicylic acid or benzoyl peroxide, which can cause skin irritation, according to Dr. Nussbaum), you can also simply incorporate one of these devices into your regular skincare routine. Include blue light therapy at home to complement traditional acne products and gain an additional advantage, suggests Dr. Zeichner. For mild acne, light therapy may even be effective on its own, he adds.

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