Can Red Light Therapy Speed Up Wound Healing? What a Diabetic Foot Ulcer Trial Found
This page summarizes published research for general education. It isn't medical advice and doesn't replace guidance from your doctor.
Slow-healing wounds — especially diabetic foot ulcers — are a serious problem: they're painful, prone to infection, and a leading cause of lower-limb amputation. Red light therapy (photobiomodulation) has been studied as a non-drug way to support the body's own healing process, and a 2024 randomized controlled trial put it to the test in real patients.
What the research looked at
Researchers at the University of São Paulo ran a controlled randomized clinical trial on adults aged 30–65 with grade I or II diabetic foot ulcers, using at-home red and infrared LED devices. Wound area, temperature, sensitivity, and pain were tracked at baseline and again at 30, 60, and 90 days, with a follow-up 30 days after treatment ended.
What they found
Both wavelengths produced large reductions in ulcer size compared to the control group — red LED showed a strong effect (effect size d=1.7) and infrared LED an even slightly stronger one (d=1.6, with an additional advantage over red of d=0.4). In plain terms: both colors of light meaningfully shrank the wounds, with infrared edging out red light overall.
What this means in practice
This is one trial, not a large-scale confirmation, but it adds to a growing body of photobiomodulation wound-healing research. If you have a diabetic ulcer or any slow-healing wound, this isn't a substitute for wound care from a doctor or podiatrist — but it's a reasonable non-drug addition to discuss with them, particularly given how few side effects light therapy carries compared to other interventions.
