Red Light Therapy
Red (630 to 680nm) and near-infrared (800 to 880nm) wavelengths penetrate tissue to stimulate ATP production, collagen synthesis, and cellular repair. The most-studied application of photobiomodulation.
Red light therapy uses red light at 630 to 680nm and near-infrared light at 800 to 880nm. The strongest trials cover skin collagen and pattern hair loss. Pain relief has real but modest support. Claims about hormones, fat loss and the thyroid have no trial support. Read what it is first, then the dosing guide before you buy a device.
Before you buy a device, work out your session time with the dosing calculator and compare measured output in the device database.
What the evidence supports
Grades come from the trials each guide cites. Follow a row to the evidence.
All guides (10)
How Often Should You Use Red Light Therapy?
Session frequency depends on your goal and condition: what the clinical trials used, why some applications need rest days, and how to build a schedule you'll keep.
Apr 21, 2026
ReadRed Light Therapy Dosing Guide: How to Calculate J/cm²
Dose in joules per cm2 determines whether red light therapy works. How to calculate it, what ranges the evidence supports, and why most people underdose.
Apr 20, 2026
ReadRed Light Therapy at Home vs. Professional Treatment: An Honest Comparison
Clinical red light therapy devices cost $5,000–$50,000 and are used by trained practitioners. Consumer panels cost $200–$3,000. What the price gap does and doesn't buy you in results.
Apr 19, 2026
ReadRed Light Therapy Side Effects, Dangers, and Contraindications
Red light therapy is low-risk, but real dangers and contraindications exist. What the side effects are, who should avoid it, and the honest state of the safety evidence.
Apr 18, 2026
ReadHow to Use Red Light Therapy: Distance, Duration, and Protocol
Getting red light therapy right comes down to four variables: wavelength, irradiance, dose, and consistency. How to set a protocol that matches the clinical evidence.
Apr 17, 2026
ReadRed Light Therapy for Hair Growth: FDA-Cleared and Evidence-Based
Laser caps are among the few consumer hair-loss devices with real FDA 510(k) clearance and sham-controlled trials. The mechanism, the RCT evidence, and the limits.
Apr 16, 2026
ReadWhat Is Red Light Therapy? A Clear, Science-Based Explanation
Red light therapy uses specific wavelengths of light to trigger cellular energy production: the mechanism, what the research supports, and what it doesn't.
Apr 15, 2026
ReadRed Light Therapy for Pain: The Evidence by Condition
Red and near-infrared light therapy reduces pain in several musculoskeletal conditions with controlled trial support. What works, what doesn't, and the doses that matter.
Apr 14, 2026
ReadRed Light Therapy for Skin: What the Evidence Actually Shows
Red light therapy has stronger clinical evidence for skin than almost any other application: what it does for collagen, wrinkles, and wound healing, and what it can't.
Apr 13, 2026
ReadRed Light Therapy Benefits: What Science Says vs. What's Hype
A breakdown of the most researched benefits of red light therapy: skin health, pain relief, hair growth, and workout recovery, with the actual evidence for each.
Apr 11, 2026
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