Red Light Therapy: All You Need To Know
RED LIGHT THERAPY: ALL YOU NEED TO KNOW
Last updated: April 2026
If you've been hearing more about red light therapy lately, you're not imagining it. What was once a niche recovery tool used by elite athletes and dermatologists has quietly become one of the most evidence-supported approaches to improving sleep quality — and it's simpler to use than most people expect.
Here's everything you need to know.
What Is Red Light Therapy?
Red light therapy — also known as photobiomodulation — is a non-invasive treatment that exposes the body to low-wavelength red and near-infrared light. Unlike UV light, which can damage skin, red light wavelengths (typically 600–700nm) penetrate the skin's surface safely and interact with cells at a biological level.
Originally developed by NASA to support plant growth in space, researchers quickly discovered its therapeutic effects on the human body — from accelerating wound healing to reducing inflammation and, critically, improving sleep.
How Does It Affect Sleep?
The connection between red light and sleep comes down to your circadian rhythm — your body's internal 24-hour clock that governs when you feel alert and when you feel sleepy.
Your circadian rhythm is heavily influenced by light. Bright, blue-spectrum light (like sunlight, or the light from your phone screen) signals wakefulness. As evening approaches, your body expects light to dim and shift warmer — triggering the release of melatonin, the hormone that prepares you for sleep.
The problem? Modern life keeps us bathed in blue-spectrum light well into the night. Overhead lights, screens, and even energy-efficient bulbs all suppress melatonin at exactly the time your body needs it most.
Red light doesn't have this effect. Because it sits at the warmer end of the light spectrum, it doesn't interfere with melatonin production. In fact, research suggests it may actively support it — helping your body wind down more naturally and fall asleep faster.
What Does the Research Say?
A study published in the Journal of Athletic Training found that participants who used red light therapy experienced significantly improved sleep quality and duration. Research in the Journal of Photochemistry and Photobiology similarly highlighted its effectiveness in supporting the body's natural sleep-wake cycle.
While research is ongoing, the evidence consistently points in the same direction: reducing blue light exposure and introducing red light in the evening supports deeper, more restorative sleep.
How to Use It
Red light therapy for sleep is most effective when used consistently in the 20–30 minutes before bed. Place your device on a bedside table, dim your overhead lights, and let it run while you wind down — reading, stretching, or simply decompressing from the day.
Pair it with a few simple habits for best results: keep your room cool, avoid screens in the final hour before sleep, and try to go to bed at a consistent time each night.
The goal is to give your body the environmental cues it needs to do what it's designed to do — rest deeply and wake up recovered.
The Bottom Line
Red light therapy isn't a sleep hack or a shortcut. It's a way of working with your biology rather than against it — giving your body the light signals it evolved to expect, at the time of day it needs them most.
For anyone whose sleep has been disrupted by the demands of modern life — late nights, early mornings, the relentless pull of screens — it's one of the most practical and evidence-backed tools available.
Explore the Night Switch™ — Circadian Sleep's red light therapy device, designed for simple, effective use every evening.