Quick answer: Light therapy can help mild-to-moderate acne — but the colours do different jobs. Blue light (around 415 nm) targets acne bacteria, while red light (630–660 nm) mainly calms inflammation and redness. Many acne devices combine both. It’s a useful add-on, not a replacement for a dermatologist’s plan for severe acne.
Red vs blue light for acne
Blue light reduces C. acnes bacteria on the skin; red light soothes the inflammation that makes breakouts red and swollen. Combination devices aim to do both at once.
What red light does
On its own, red light won’t clear bacteria, but it can reduce redness and support healing after breakouts, and it’s gentle on skin.
When to see a dermatologist
Cystic, scarring, or persistent acne needs medical treatment — light therapy is an adjunct, not a cure. General wellness information, not medical advice.
Related answers
Shopping for a device? See our red light therapy picks, or start with the complete red light therapy guide. General wellness information, not medical advice.
FAQ
Is red or blue light better for acne?
Blue light targets acne bacteria; red light calms inflammation. Combination devices use both.
Can red light therapy clear acne alone?
It mainly reduces redness and inflammation; for active breakouts, blue light or medical treatment does more.
Considering a mask? See what to look for in a red light face mask.