Oui, red and blue light therapy has been shown to work in clinical trials. But how well it works depends on the condition being treated, the device used, and how it’s applied. Here’s what the science says:
The science says that blue light therapy (415–450nm) works for the following:
Acne treatment
It kills P. acnes bacteria (this has been approved by the FDA for mild-to-moderate acne).
Study: 60–70% reduction in acne after 8–12 sessions (Journal of Clinical and Aesthetic Dermatology).
Oily Skin Control
Reduces sebum production temporarily.
There is limited or no evidence for the following:
Wrinkles, scarring, or fat loss.
2. Thérapie par la lumière rouge (630–660nm)
Proven for:
It can help wounds heal and boost collagen production. FDA-approved for minor wounds and arthritis pain.
Study: 36% increase in collagen after 30 sessions (Photomedicine and Laser Surgery).
Joint and muscle pain relief
Reduces inflammation in osteoarthritis (NIH-supported research).
Hair growth
Can improve hair loss (FDA-cleared devices like iRestore).
⚠ Mixed/Weak Evidence for:
Weight loss (only temporary “inch loss” in studies).
Depression or cognitive benefits (early-stage research).
How well do they work together?
For acne:Blue + red combo is better than blue alone (77% vs. 50% improvement in one trial).
Red light reduces redness and scarring after acne.
For anti-ageing:
Red light is more effective (blue light only has a small effect).
⚠️ Important limitationsDevice quality matters
Cheap Amazon LEDs (<$100) lack the right levels of light (mW/cm²) for clinical results.
Look for FDA-cleared devices (Par exemple, Merican Red Light Therapy Bed M4N).
It is important to be consistent.You will need to do 3–5 sessions a week for 4+ weeks to see results.
It’s not a magic solution.It works best as an extra therapy, for example together with retinoids for acne or exercise for fat loss.
🚦 Realistic ExpectationsCondition Red Light Blue Light ComboAcne 🟡 (Redness) ✅ (Bacteria) ✅✅Wrinkles ✅ ❌ ✅Pain Relief ✅ ❌ ❌Hair Growth ✅ ❌ ❌Fat Loss 🟡 (Temporary) ❌ ❌The VerdictYes, They work for some things (like acne, healing wounds and reducing pain).They won’t replace treatments from your dermatologist, such as tretinoin or lasers.You’ll get the best results from medical-grade devices and you’ll need to be patient.For acne, it’s worth trying a combination of treatments. For anti-ageing, focus on red light therapy and skincare.Here is an example of using red light therapy bed before and after.
