Blue plus red light for acne, compared with benzoyl peroxide

What they did

107 people were randomly assigned to blue light (415 nm), mixed blue and red light (415 nm and 660 nm), plain white light, or 5% benzoyl peroxide cream. The light groups used portable lamps for 15 minutes a day for 12 weeks.

Assessors comparing the light groups did not know which light each person used. That blinding was not possible for the cream group.

What they found

After 12 weeks, blue plus red light reduced inflamed spots by an average of 76%. That was better than white light at every check, better than benzoyl peroxide at weeks 8 and 12, and better than blue alone at weeks 4 and 8, though not at week 12.

Blackheads and whiteheads improved by 58% with blue plus red, more than with the other options, but that difference was not statistically clear. No significant short-term side effects were seen.

What it cannot tell you

The trial used daily sessions, which is more frequent than some home masks recommend. It covered mild to moderate acne only.

In short

A frequently cited acne trial. The combination of blue and red light did more than either white light or, by the end, a standard benzoyl peroxide cream.

Masks with these wavelengths

Four of the 10 masks in the comparison list a wavelength in every band used here (blue near 415 nm and red, 620–670 nm). They are examples, listed alphabetically, each with our specification page and the manufacturer’s own product page. They are not recommendations, and the links carry no affiliate parameters.

• CurrentBody Skin LED Face Mask Series 3415 · 532 · 590 · 633 · 830 · 1072 nm · CurrentBody product page
• Dr. Dennis Gross DRx SpectraLite FaceWare Pro415 · 630 nm · Dr. Dennis Gross product page
• Shark CryoGlow FW312415 · 630 · 830 nm · Shark product page
• Therabody TheraFace Mask Glo415 · 633 · 830 nm · Therabody product page

These masks list one of the bands, but not all:

• CurrentBody Skin LED Mask Series 2633 · 830 · 1072 nm · CurrentBody product page
• Dr. Renú SpectraLift Advanced465 · 530 · 630–660 · 850 nm · Dr. Renú product page
• Nanoleaf LED Light Therapy Face Mask460 · 520/525 · 640 · 850 nm · Nanoleaf product page
• Omnilux Contour Face633 · 830 nm · Omnilux product page
• Silk’n LED Face Mask 100463 · 592 · 633 nm · Silk’n product page
• The Light Salon Boost LED Face Mask (Boost Advanced)633 · 830 nm · The Light Salon product page

Matching a wavelength is not the same as matching the study. Dose, irradiance, session length and schedule also differ, and a mask’s reported output is not independently measured. See how dose works and home vs clinic doses.