A poor night’s sleep can affect your entire day. Waking up tired, struggling to concentrate, feeling irritable, or being unable to unwind in the evening are issues far more common than you might think.
What many people don’t realize is that light is one of the most powerful factors influencing your sleep rhythm. That’s where light therapy comes in, but how does it work?
Note: The text below is not medical advice. It is based on our own knowledge, user experiences, and various scientific sources.
Table of Contents
What is light therapy and how does light affect your sleep?
Light therapy uses specific wavelengths of light to support your biological rhythm. During the day, bright light helps your body stay awake and alert. In the evening, your body needs calming light that doesn’t disrupt melatonin production.
Light is the most important “time cue” for your internal clock. When your body receives the right light at the right time, your sleep-wake cycle functions optimally. At Liroma, we use high‑quality red light therapy lamps designed to support these mechanisms.
How your biological clock (circadian rhythm) works
In your brain lies the suprachiasmatic nucleus, the center that determines when you should be awake and when you should sleep. This rhythm is regulated by:
- Melatonin: the hormone that makes you sleepy
- Cortisol: the hormone that keeps you alert
- Light signals: especially blue light suppresses melatonin and keeps you awake
When this rhythm becomes disrupted, due to screen use, irregular work hours, or limited daylight, sleep problems arise.
How does blue light affect your sleep?
Blue light (400–500 nm), emitted by phones, laptops, TVs, and many artificial light sources, strongly suppresses melatonin. It signals to your brain that it’s “daytime,” even when it’s dark outside.
Consequences of too much blue light in the evening:
- Difficulty falling asleep
- Restless sleep
- Disrupted sleep cycles
- Daytime fatigue
Reducing blue light exposure in the evening is one of the most important steps toward better sleep.
Does red light help you sleep better?
Red light (610–750 nm) has a completely different effect on your body than blue light. It:
- does not suppress melatonin,
- promotes relaxation,
- reduces alertness,
- supports the body’s recovery processes.
Red light gently penetrates the skin and stimulates cells to function more efficiently, without activating the brain the way blue light does. This makes red light ideal for evening use, both as lighting and as therapy.
View all red light therapy panels
What does science say?
Although research is still developing, several promising studies exist:
- 2012 – Chinese female athletes: Red light (30 min/day for 14 days) improved sleep quality, melatonin levels, and endurance.
- A small 2017 study suggested that light color plays a significant role in falling asleep, and personal preference may influence which color works best.
- 2021 – Light and circadian sensitivity: Red light activates the biological clock far less than blue light, making it suitable for evening use without disrupting your rhythm.
Important: red light does not actively induce sleep like a sleeping pill, but it does not disrupt your rhythm and creates ideal conditions for naturally falling asleep.
Does light therapy help with specific sleep disorders?
Delayed Sleep Phase Disorder (DSPD)
People with DSPD fall asleep late and wake up late. Morning light therapy helps shift the rhythm earlier.
Advanced Sleep Phase (ASP)
Here, you become sleepy too early and wake up too early. Evening light therapy helps delay the rhythm.
Seasonal Affective Disorder (SAD)
Due to lack of daylight in winter, the rhythm becomes disrupted. Light therapy reduces depressive symptoms and improves sleep quality.
How to use the lamps
- Morning light: 20–30 minutes of bright light to stabilize your rhythm.
- Red light in the evening: 30–60 minutes for relaxation.
- Avoid bright blue light in the evening.
- Use eye protection with certain devices.
- Consistency is key: daily use delivers the best results.
Practical tips for better sleep
- Avoid screens 1–2 hours before bedtime
- Use red light in your bedroom
- Get morning sunlight or use a daylight lamp
- Keep your bedroom cool and dark
- Maintain consistent bedtimes
- Create a calming evening routine
Conclusion
Light therapy is a powerful, scientifically supported way to improve your sleep. By using morning light and red light in the evening, you can restore your biological clock, support melatonin production, and wake up feeling refreshed.
Red light is safe, relaxing, and a valuable addition to your evening routine.
