Maybe you’ve spotted stars like Jessica Alba, Kourtney Kardashian or Chrissy Teigen on the ’gram, sporting what look like strangely backlit hockey masks from the future (in reality: they’re LED masks). Perhaps you’ve heard celebrity aestheticians hype the virtues of phototherapy, or noticed blue light on the menu at your favourite medi-spa. And maybe you’ve read headlines on how the blue light from your phone and computer is aging your skin(!). Still feel (ahem) in the dark about it all? We asked the pros to answer your most frequently asked questions about light-based beauty treatments.

What is phototherapy for the skin? What are the benefits of phototherapy?

Phototherapy (or light therapy) is an umbrella term covering a pretty wide array of light-based beauty treatments, with LEDs, IPL and lasers being the main three categories, according to Toronto dermatologist Dr. Martie Gidon. You can now get light therapy through both at-home gadgets and in-office procedures, and depending on what exactly you’re doing, phototherapy treatments can range from gentle and virtually no-risk to aggressive (expect downtime); likewise, the specific benefits vary widely, too. Here’s a quickie breakdown of the different phototherapy categories:

  • LEDs (or light-emitting diodes) give off visible light, which is exactly what it sounds like: light you can see with your own eyes. You probably know LEDs best as the energy-efficient bulbs you can get for your home, but LEDs for beauty most commonly include blue light for acne-fighting, as well as red light for anti-aging (more on those later).
  • IPL (or intense pulsed light) is a type of very bright, non-coherent light that gets absorbed by your skin’s red pigment, brown pigment and collagen. These beams are commonly used to treat inflammatory conditions (like rosacea) and dark spots, as well as smooth fine lines and wrinkles.
  • Lasers are a type of coherent light that delivers heat into skin, resurfaces skin or targets certain pigments. They can be used for a range of purposes, including reducing wrinkles, fading scars, correcting uneven pigmentation, permanently nixing hair and more.

What is blue light therapy? How does blue light for acne work?

Blue light comes from LEDs, which emit non-thermal (heatless) wavelengths of visible light. “The light is converted into energy that cells use in metabolism to help repair or regenerate cells,” explains Gidon. “Different wavelengths of light act on different mechanisms within the cells.” What is blue light, then? If you want to get technical, it’s visible light from 380 to 500 nanometers on the spectral range. As this blue light is absorbed, “it destroys acne-causing bacteria in the skin,” says Gidon.

So, how effective is blue light therapy for acne? Expect a mild treatment overall, says  Gidon. Likewise, Dr. Stephen Mulholland, founder of SpaMedica, the Toronto dermatology medi-spa and plastic surgery clinic, ranks blue light among the “entry-level light-based treatments” you can get. “It works in very mild acne,” he says. If you’re dealing with a more severe case of breakouts, blue light alone isn’t likely to cut it.

What is red light therapy? How does red light therapy work?

Like blue light, red light from LEDs is a form of low-level light therapy, but these wavelengths are in the spectral range of 630 to 660 nanometers. Red light is able to penetrate deeper into skin than blue light can, where it “stimulates fibroblasts to promote collagen production and may reduce the appearance of fine lines,” says Gidon, noting that getting treated with red light also “calms irritation and speeds up the healing process.”

How well does red light therapy work? It’s not as effective as IPL or laser treatments, says Gidon, though you can get treated with a photosensitizing medication before you get red or blue light to make it more aggressive (see below for how this works). It’s also safe to do red or blue light in combination with other cosmetic procedures, like chemical peels.

For blue light therapy and red light therapy, how many treatments do I need?

For best results with LED therapy in office, expect to go for a series of sessions: Each will typically be about 20 minutes long, and you’d usually go every one to two weeks for six treatments, followed by a maintenance visit every one to two months, says Gidon. For a more aggressive in-office LED treatment, you can opt to have your skin topically prepped with a photosensitizing medication (this makes your skin more sensitive to light). For instance, if a drug called aminolevulinic acid (ALA) is applied to your face, your blue light treatment will be more effective. Using methyl aminolevulinate (MAL) will make red light more potent, too. This kind of combo—pairing a photosensitizing drug with light—is known as “photodynamic therapy.”

Are there drawbacks to using blue light and red light?

The main downside is that these treatments are low-level light therapy, so effects won’t be dramatic. The key advantage, though, is that LED phototherapy is known for being painless and safe for all skin types, says Gidon. It’s nonablative and nonthermal, meaning it doesn’t do damage to or heat up the skin. You could squeeze it in as a speedy lunchtime procedure, since downtime is minimal to zero, and you shouldn’t experience side effects like redness, peeling or swelling. Exception: If your phototherapy is combined with a topical skin-sensitizing medication like the aforementioned ALA, you may feel a little stinging or burning during treatment, and see some redness afterwards.

Does at-home blue light or red light work as well as in-office light therapy?

You can now find at-home gadgets featuring blue light or red light—and sometimes both in the same device. For instance, there are futuristic-looking full-face masks, like the Neutrogena Light Therapy Acne Mask, which you’d wear for daily 10-minute sessions to tame breakouts. Then there are multi-duty gadgets like the Foreo UFO, which is reminiscent of a mini Roomba that you’d glide all over your face. Doing this as a 90-second treatment will give skin a dose of red, green and blue LEDs. (Green light is less common than the other two, but it’s used for brightening.)

Because they’re designed for DIY-ing, at-home gizmos are indeed less powerful than the machines you’d find at your dermatologist’s office, so think of them as a budget-friendly option for maintenance in between pro appointments.

What is blue light from electronic devices? Can blue light age your skin, too?

You may have heard that the perpetual glow of your iPhone will not only keep you up at night, but also take a toll on your skin. That’s because digital devices, including smartphones, tablets and laptop screens, give off blue light (also known as high-energy visible light, or HEV light). Some experts believe HEV can cause skin to age prematurely. But why is blue light from our tech possibly damaging, when blue light is also being used for skincare treatments? “Individuals spend many hours each day in front of computer and phone screens as opposed to minutes during blue light treatments,” says Gidon, adding that blue light can cause the generation of skin-damaging free radicals.

What ingredients prevent skin damage from blue light emitted by electronic devices? 

Ingredients that purportedly protect against HEV light are popping up in a growing number of skincare products. Noted celebrity facial plastic surgeon Dr. Jean-Louis Sebagh puts fractionated melanin—the first cosmetic ingredient designed to absorb, and protect skin from, HEV light—in many of his products, including Dr. Sebagh Supreme Day Cream. You can also find fractionated melanin in sunscreens like Zo Skin Health Oclipse Sunscreen + Primer SPF 30 and Niod Survival 30.

Beyond fractionated melanin, “topical antioxidants and broad-spectrum sunscreens also containing iron oxide protect from ultraviolet, visible and infrared lights,” says Gidon. Made-in-Canada beauty brand Céla’s new Essential Face Moisturizer, for instance, is made with an antioxidant ingredient dubbed InfraGuard (a combo of sunflower sprout and tara tree fruit extracts). It helps neutralize free radicals and protects against both infrared and HEV light. As for the damage that’s already been done, Estée Lauder’s Advanced Night Repair Eye Supercharged Complex contains 10 times the concentrated repair technology of its predecessor to reverse the effects of the modern world, namely those of blue light and pollution.

Why is UV light bad for skin, if other forms of light have beauty benefits?

Different wavelengths of light have different effects, which is why baking at the beach has a totally different impact on your skin than getting a dose of phototherapy from your derm. “What’s really bad for your skin from the sun is ultraviolet light. Ultraviolet light B and A [UVB and UVA] are the ones that cause what are called thymine dimers, or changes in the DNA of your skin,” explains Mulholland. These DNA changes can raise your risk of skin cancer, and sun damage is also to blame for prompting premature signs of aging, like wrinkles, dark spots and sagging. That’s why using SPF faithfully remains the single most important thing you can do for your skin health. (Head over here for how to pick the best sunscreen for you.)

What are the best blue light (and blue light–protecting) products?

Foreo UFO, $349, sephora.ca

Best LED Device to Reverse Aging

Meant to enhance Foreo’s sheet masks, the cool gadget combines LED wavelengths with sonic pulsations to smooth and brighten.

 

Neutrogena Light Therapy Acne Mask, $50, shoppersdrugmart.ca

Best Light Therapy Mask for Fighting Acne

Pop this at-home mask on for 10 minutes a day to help minimize breakouts.

 

Dr. Sebagh Supreme Day Cream, $257, saksfifthavenue.com

Best Cream for HEV Light Protection

Shield your skin from the harmful HEV light emitted by laptops, smartphones and tablets.

 

Céla Essential Face Moisturizer, $78, thisiscela.com

Best Daily Defence Moisturizer

The refreshing gel cream keeps skin hydrated while protecting it against infrared and HEV light.

 

NIOD Survival 30, $30, niod.com

Best Environmental Damage Protector 

Stand up to environmental stressors like infrared and blue light (as well as smog and pollution) with this high-protection sunscreen.

 

Estée Lauder Advanced Night Repair Eye Supercharged Complex, $80, esteelauder.ca

Best Eye Cream to Repair Blue Light Damage

It’s specifically formulated to reverse the damage blue light may cause to the delicate eye area.

 

Zo Skin Health Oclipse Sunscreen + Primer SPF 30, $70, zoskinhealth.ca

Best Sunscreen with Fractionated Melanin

A sunscreen-primer hybrid that protects against UVA and UVB rays as well as HEV light.

 

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