What is blue light and why does it affect your sleep?

Blue light is part of the visible light spectrum — specifically the shorter wavelengths between 400 and 500 nanometres. Blue light occurs naturally in daylight and helps us stay alert and awake.

But when we’re exposed to blue light in the evening, it can have a negative effect on our sleep.

Blue light affects the body’s production of melatonin, the hormone that regulates our circadian rhythm and helps us fall asleep.

When you’re exposed to blue light at night, melatonin production is suppressed, which delays sleep and disrupts your sleep quality.

Studies have shown that even short periods of blue light exposure before bed can delay sleep onset and reduce sleep depth.

The biological mechanism behind blue light’s effect on sleep

The reason blue light has such a strong effect on sleep is that it directly affects the body’s biological clock, also known as the circadian rhythm. Specialised cells in the retina, called intrinsically photosensitive retinal ganglion cells (ipRGCs), are particularly sensitive to blue light. When blue light reaches these cells, they send a signal to the brain’s hypothalamus, which then suppresses melatonin production. Read more about it on Oxford Academic.

Interestingly, blue light affects not only the timing of sleep but also its quality and duration. Studies have shown that people exposed to blue light in the evening tend to experience a delayed sleep phase and often wake earlier than they’d like.

Why clear glasses can be enough for some people

Many people today wear clear or lightly tinted blue light glasses to reduce daily exposure to blue light from screens and artificial lighting. These glasses can filter out part of the harmful blue light, especially in the high-frequency range (between 400–450 nm), which is most strongly associated with sleep disturbances and eye strain.

For people who use screens during the day, clear blue light glasses are a great option. They help reduce eye strain and minimise some of the negative effects of artificial lighting — without changing how colours look. Studies suggest that clear glasses can reduce blue light exposure enough to alleviate symptoms like dry eyes, fatigue and headaches that often come with long screen sessions.

Red glasses: the ultimate solution for blue light in the evening

For people with more serious sleep issues, or anyone wanting maximum protection against blue light, red or amber glasses are the best solution. Red lenses block almost the entire spectrum of blue light, and several studies have shown that these glasses can effectively prevent the melatonin-suppressing effect of blue light.

A study at Columbia University found that people who wore amber lenses for two hours before bed experienced 30 minutes more sleep and improved sleep quality compared to those wearing clear lenses. That makes red glasses particularly effective for anyone who spends a lot of time in front of screens in the evening, or who is sensitive to changes in light.

Which glasses are right for you?

Whether to choose clear or red lenses depends on your individual needs. If you only want a little extra protection during the day or while using a computer, clear blue light glasses are a great choice — they reduce eye strain without disrupting how you perceive colours, and they fit comfortably into your daily routine.

If you have more persistent sleep issues, or want maximum protection in the evening, red glasses are the most effective option. They offer a higher degree of blocking and ensure your melatonin production isn’t disrupted, which can improve both sleep onset and sleep quality.

Whichever option you choose, using blue light glasses correctly can be a valuable tool for improving your sleep and protecting your circadian rhythm in a time when artificial light is unavoidable.

Protect your eyes with our Blue Light glasses

If you’re ready to protect your sleep and reduce eye strain, our blue light glasses are an excellent choice.

• For maximum protection in the evening, our 98% blue light glasses are the ideal pick. These red-tinted lenses block almost all blue light and are designed to support sleep by ensuring your melatonin production isn’t disrupted.
• For milder protection, like during the workday, we also offer 30% blue light glasses. These reduce a meaningful share of harmful blue light without affecting colour perception, which makes them perfect for daytime use, where you still want colours to look natural.

Whichever type you choose, our glasses help protect your eyes and improve your sleep quality.