What Is Red Light Therapy and Does It Work?

Introduction

Red light therapy (RLT) is one of the fastest-growing wellness technologies — and for good reason. Once confined to clinical settings, it's now available as a safe, non-invasive treatment you can use at home. But with so much noise online, it's fair to ask: does red light therapy actually work?

In this guide, we break down the science, the evidence, and what you can realistically expect.

What Is Red Light Therapy?

Red light therapy — also called photobiomodulation (PBM) or low-level laser therapy (LLLT) — uses specific wavelengths of red and near-infrared (NIR) light to penetrate the skin and stimulate cellular processes.

The key wavelengths used in clinical and consumer devices are:

• Red light (630–700 nm) — absorbed by the skin's surface layers, supporting collagen production, skin tone, and wound healing.
• Near-infrared light (800–880 nm) — penetrates deeper into muscle, joint, and nerve tissue, supporting recovery and reducing inflammation.

Unlike UV light (which damages DNA) or heat-based treatments, red and NIR light work at a cellular level without causing harm to tissue.

How Does It Work? The Science of Photobiomodulation

The mechanism behind RLT is well-established in peer-reviewed research. Here's what happens at a cellular level:

1. Light is absorbed by mitochondria. Specifically, a protein called cytochrome c oxidase absorbs red and NIR photons.
2. ATP production increases. This boosts the cell's energy currency (adenosine triphosphate), giving cells more fuel to repair and regenerate.
3. Reactive oxygen species (ROS) are modulated. This reduces oxidative stress and inflammation.
4. Gene expression changes. Cells upregulate proteins involved in repair, collagen synthesis, and anti-inflammation.

The result? Faster cellular repair, reduced inflammation, and improved tissue function — across a wide range of body systems.

What Does the Research Say?

Red light therapy has been studied in hundreds of peer-reviewed clinical trials. Here's a summary of the strongest evidence:

• Skin health: Multiple studies show significant improvements in collagen density, skin elasticity, and reduction in fine lines after consistent use. A 2014 study in Photomedicine and Laser Surgery found measurable improvements in skin complexion and collagen content after 30 sessions.
• Muscle recovery: A 2016 meta-analysis in Lasers in Medical Science found RLT significantly reduced muscle fatigue and soreness when applied before or after exercise.
• Joint pain and inflammation: The World Association for Laser Therapy (WALT) has published dosage guidelines for RLT in treating conditions including arthritis and tendinopathy.
• Hair growth: A 2013 randomised controlled trial found RLT significantly increased hair density in men and women with androgenetic alopecia.
• Sleep and mood: Emerging research suggests RLT may support circadian rhythm regulation and reduce symptoms of seasonal affective disorder (SAD).

It's worth noting: results vary depending on device quality, wavelength accuracy, treatment duration, and consistency. Not all devices are equal.

What Red Light Therapy Is Not

RLT is not a miracle cure. It works best as part of a consistent wellness routine. It won't replace medical treatment for serious conditions, and results typically take 4–12 weeks of regular use to become visible.

It's also not the same as:

• Infrared saunas (which use heat, not light)
• UV tanning beds (which damage skin)
• LED face masks with random colours (which may lack therapeutic wavelengths)

Device quality matters enormously. Look for devices that specify their wavelengths, irradiance (mW/cm²), and have relevant safety certifications.

Is Red Light Therapy Right for You?

RLT is suitable for most healthy adults. It's non-invasive, painless, and has an excellent safety profile when used correctly. Common use cases include:

• Improving skin tone, texture, and reducing fine lines
• Supporting muscle recovery after exercise
• Reducing joint discomfort
• Stimulating hair growth
• General cellular health and energy

If you're on photosensitising medication, pregnant, or have a diagnosed light-sensitive condition, consult your GP before starting.

Explore Kroma Red Light Therapy Devices

At Kroma, we design premium red light therapy devices built around clinically relevant wavelengths and professional-grade irradiance — so you get results, not just light.

• Kroma Glow Pro — our flagship full-body panel for skin and recovery
• Kroma Radiance Pro — targeted red light for face and body
• Kroma Revive Mat — full-body coverage for recovery and relaxation
• Kroma Glow Mask — hands-free NIR mask for facial rejuvenation
• Kroma Hair Therapy — targeted scalp treatment for hair growth

The Bottom Line

Red light therapy is backed by a substantial and growing body of clinical evidence. When used consistently with a quality device, it can deliver real, measurable benefits for skin, recovery, pain, and more. It's not magic — it's mitochondria.

Ready to start? Browse our full range of Kroma devices and find the right fit for your goals.

 

Wondering about safety? Read our guide: Is Red Light Therapy Safe?"