Clinical data

LED photobiomodulation (PBM) is a non-invasive light therapy that uses low-energy, non-thermal light at specific wavelengths to stimulate the skin's natural repair processes. In recent years, dozens of randomized clinical trials and systematic reviews have been published examining the effects of LED therapy on photoaging, wrinkles, acne, scars, wounds, and inflammatory skin conditions.

The main mechanisms, wavelengths, and key clinical studies are summarized below, supported by links to PubMed, PMC, and peer-reviewed journals.

What is LED photobiomodulation?

LED therapy uses light in specific wavelengths (most commonly red, blue, yellow, and near-infrared) that is absorbed by mitochondria in cells. This results in:

  • increased production of ATP (cellular energy);
  • modulation of inflammatory processes;
  • stimulation of collagen and elastin synthesis;
  • supporting tissue regeneration and repair.

A review of the available data on LED in dermatology and clinical experience was published by Opel et al.:
Light-emitting Diodes: A Brief Review and Clinical Experience (PMC)

A more recent review of red light therapy and its mechanisms (including fibrosis and scarring) was published by Austin et al.:
Red Light Phototherapy: Mechanisms and Clinical Applications (PMC)

Main wavelengths and effect on the skin

Red light (~630–660 nm)

  • It penetrates to the dermis – the layer where collagen and elastin fibers are located.
  • Stimulates the synthesis of collagen and elastin.
  • Improves fine lines, wrinkles and overall skin texture and elasticity.

Overview and clinical data on red light and photorejuvenation:
Opel DR et al., LEDs in dermatology (PMC)

Near infrared light (~800–850 nm)

  • Penetrates deeper into tissues.
  • Supports tissue repair and collagen remodeling.
  • It is used for photoaging, scars and recovery after procedures.

Overview of mechanisms and data for red and near-infrared light:
Austin E. et al., Red Light Phototherapy (PMC)

Blue light (~415–450 nm)

  • Targets the bacteria Cutibacterium acnes (formerly Propionibacterium acnes ) and the sebaceous glands.
  • Suitable as a complementary therapy for mild to moderate acne.
  • It is often combined with red light for a better anti-inflammatory effect.

Overview of light-based acne therapies (LED, IPL, lasers):
Pei S. et al., Light-based therapies for acne (PMC)

Yellow/amber light (~580–600 nm)

  • It affects the more superficial vessels and microcirculation.
  • It is used to reduce redness and sensitivity.
  • Promotes a more even complexion and a "glow" effect.

Overview of clinical applications of yellow and other LED wavelengths in dermatology:
Opel DR et al. (PMC)

How many clinical trials are there?

If we include more recent studies on at-home LED devices for the face, neck, and acne, the number of clinical studies now exceeds the widely used marketing claims of “40+ clinical studies.”

1. LED therapy for anti-aging effect (wrinkles, texture, elasticity)

Periocular wrinkles – wrinkles around the eyes

  • Mota LR et al., 2023 – split-face, randomized controlled trial with 137 women. Red (660 nm) and yellow (590 nm) LED light were used, 10 sessions over 4 weeks. Result: about 30% reduction in periorbital wrinkle volume and improvement in texture.
    PubMed - periocular wrinkles and LED

Full face – photorejuvenation and collagen

  • Wunsch A. et al., 2014 – randomized controlled trial with red and near-infrared light (633/830 nm) on large areas (face and body). Improvement in fine lines, smoothness and density of the dermis was reported.
    Photobiomodulation for skin rejuvenation (PMC)

Photorejuvenation with photosensitive gel + LED (KLOX)

  • Nikolis A. et al., 2016 – randomized, placebo-controlled, split-face clinical trial with LED device and photosensitive gel. Result: significant improvement in wrinkles and texture compared to the control side.
    KLOX LED phototherapy for skin rejuvenation (PMC)

Home LED facial device (photoaging)

Overview of clinical experience with LED for photoaging

2. LED therapy for neck and décolleté

Neck wrinkles – home remedy

  • Park SO et al., 2025 – randomized, double-blind study with 70 participants using a home LED neck device with red and infrared light. Protocol: 9 min/day, 5 times a week. Result: significant improvement in wrinkles (Lemperle Wrinkle Scale, GAIS) compared to a sham device, and thyroid safety was also monitored.
    Home-use neck LED device (PubMed)

Long-term safety for the neck and thyroid gland

  • Lee YI et al., 2021 – daily application of an LED device (630/850 nm) to the neck for 16 weeks. Result: improvement in skin density, elasticity and hydration and no negative effect on the thyroid and parathyroid glands.
    LED neck device safety (PMC)

3. LED therapy for acne vulgaris

Combined blue and red light

  • Kwon HH et al., 2013 – double-blind, randomized controlled trial in patients with mild to moderate acne. A home device with combined blue (415 nm) and red (630 nm) light was used. Results: significant reduction in inflammatory and non-inflammatory lesions and good tolerability.
    Blue + red LED for acne (PubMed)

Blue light 414 nm + cosmetic mode

  • Ash C. et al., 2015 – Randomized controlled trial of a home blue LED device (414 nm) in combination with a cosmetic regimen. Patients achieved a significant reduction in the number of lesions compared to the control group.
    Home-use blue LED device (PubMed)

Systematic reviews of blue light and LED for acne

Overview of home LED devices for acne (JAMA Dermatology)

4. LED therapy for wounds, scars and recovery

Postoperative scars

  • Kurtti A. et al., 2021 – randomized, split-face, dose-ranging trial of red LED light for post-operative scar reduction. Results: improvement in scar appearance and texture and good safety profile.
    Red LED for postoperative scars (PubMed)

Erythema and discomfort after IPL

  • Khoury JG et al., 2008 – randomized trial in which LED photomodulation was used after IPL on photodamaged skin. Result: accelerated resolution of redness and discomfort.
    LED after IPL treatment (PubMed)

Generalized applications: wounds, radiation dermatitis, recovery

5. Great review articles about LED therapy

For a more in-depth understanding of the scope of scientific data, the following umbrella reviews can also be used:

  • Systematic review of randomized clinical trials
    Light-emitting diodes in dermatology: A systematic review of randomized controlled trials – analyzed 31 RCTs for acne, wounds, herpes, photoaging, etc.; concluded that LEDs are a promising, safe, and affordable method.
    PubMed | PMC – full text
  • Clinical applications of LED in dermatology
    Light-emitting Diodes: A Brief Review and Clinical Experience – examines red, yellow, blue, and infrared light with specific clinical examples.
    PMC – full text
  • Photobiomodulation and skin (2024)
    Unlocking the Power of Light on the Skin – a more recent review, bringing together data on lasers and LEDs for various skin conditions, with a focus on personalized parameters and safety.
    PMC – full text
  • Home LED devices for acne
    At-Home LED Devices for the Treatment of Acne Vulgaris – a review in JAMA Dermatology on the effectiveness of at-home LED devices for acne.
    JAMA Network – summary

Conclusion

Clinical data show that LED photobiomodulation is a promising, non-invasive and safe approach for:

  • reduction of fine lines and wrinkles;
  • improving skin texture, elasticity and density;
  • supporting therapy for mild to moderate acne;
  • faster recovery after procedures, wounds and scars;
  • reducing redness and sensitivity.

Devices like LED face and neck masks are designed around these wavelengths and parameters used in clinical trials. However, LED therapy is not a substitute for a dermatologist’s consultation or medical treatment for more serious conditions – it is a complementary, scientifically proven tool in the care of healthy, younger-looking skin.