The Science Behind Red Light Therapy and Better Sleep
THE SCIENCE BEHIND RED LIGHT THERAPY AND BETTER SLEEP
Last updated: April 2026
Red light therapy has earned genuine scientific credibility as a tool for improving sleep — but understanding why it works requires a brief look at the biology it's designed to support.
Your Circadian Rhythm and Why Light Matters
Your circadian rhythm is your body's internal 24-hour clock. It regulates nearly every biological process — including when you feel alert, when you feel sleepy, and how deeply you sleep when you do.
Light is the primary signal your circadian rhythm uses to stay calibrated. Specifically, it's the spectrum of light that matters. Blue and white light — the kind emitted by the sun, overhead lighting, and screens — signals daytime and suppresses melatonin, your body's primary sleep hormone. As evening approaches and light naturally dims and warms, melatonin rises and your body prepares for sleep.
When that natural light transition doesn't happen — because you're still under bright lights or looking at a screen at 10pm — your circadian rhythm stays in daytime mode. Melatonin is suppressed. Sleep onset is delayed. And even when you do fall asleep, the quality is often compromised.
Where Red Light Comes In
Red light sits at the warmer end of the visible light spectrum, typically between 620–700nm. Unlike blue light, it does not suppress melatonin. Research suggests it may actively support melatonin production by providing a light environment that's consistent with what your body expects at the end of the day.
The Night Switch™ uses two specific wavelengths:
- 660nm (red light) — absorbed by the skin's surface, this wavelength supports melatonin production and has been shown to reduce inflammation and support cellular repair
- 850nm (near-infrared light) — penetrates deeper into tissue, promoting ATP production (cellular energy), muscle recovery, and more restorative rest at a cellular level
Together, these wavelengths work with your body's biology to support the conditions needed for deep, uninterrupted sleep.
What the Research Shows
A study published in the Journal of Athletic Training found that participants using red light therapy experienced significantly better sleep quality and duration compared to a control group. Research in the Journal of Photochemistry and Photobiology highlighted its effectiveness in supporting circadian rhythm regulation and improving sleep onset.
Importantly, red light therapy is non-invasive, drug-free, and has no known side effects when used as directed — making it a practical option for anyone looking to improve their sleep without relying on supplements or medication.
Practical Application
For sleep benefits, consistency matters more than duration. Using the Night Switch™ for 20–30 minutes in the hour before bed — while dimming other light sources — gives your circadian rhythm the signal it needs to begin the wind-down process.
Over time, this consistent evening cue helps recalibrate your body clock, making it easier to fall asleep, stay asleep, and wake feeling genuinely rested.
Circadian Sleep was built on one idea: that better sleep starts with better light. The Night Switch™ makes red light therapy simple, effective, and accessible for everyday use.