Can Light Therapy Help You Sleep?

5 min read

Last Modified 1 June 2023 First Added 16 March 2021

By Liam Porter

Did you know exposing yourself to light can actually help you sleep? It may seem counterintuitive at first, but light can have a huge impact on whether or not you have a well-rested night.

Using light to aid your slumber is often referred to as light therapy. If you’re struggling to get some shuteye, this therapy can help you regain the snooze you so desperately need.

This guide will break down everything you need to know about light therapy for sleep. Let’s dive into what it is, how it works, and what you can expect.

What is light therapy and how does it help?

Light therapy involves exposure to white-blue light during the day, particularly in the morning. The idea is that many of us don’t get exposed to light in the right way, which can mess with our natural circadian rhythms.

Our 2022 Sleep Survey found that of the top 10 activities people do before bed, 6 of them include looking at screens! This means that most people are getting bright light just before bed, which can stop you from feeling sleepy.

Using tools like lightboxes to mimic daylight can help regulate your hormones and get you back on track to a restful night. This can ease the sleep-disrupting symptoms of different medical conditions such as:

It has also been found effective in research for helping shift workers who need to adjust their body clock to be alert at night.

So, what's the science behind it?

Light therapy works by tapping into and resetting your circadian rhythms. These are the natural sleeping and waking cycles the body goes through and they work in a 24-hour cycle.

When a circadian rhythm is working correctly, you’ll naturally start to feel sleepier once the sun goes down, and then awake during sunrise. If this rhythm is disrupted or skewed, you may find yourself sleeping during the day or staying up too late.

By exposing yourself to a lightbox during the day, you can start to reset your circadian rhythms. This is because the box mimics sunlight, helping to tell your body it’s time to wake up. This light is part of the production process of chemicals in your brain, such as melatonin and serotonin. In fact, there is evidence to suggest light is one of the strongest cues for circadian rhythms.

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Does light therapy work?

The science says yes! There have been many studies on the efficacy of light therapy. This meta-analysis from 2016 discovered light therapy to be effective for sleep problems in general, specifically referencing insomnia and circadian rhythms.

If you can’t incorporate light therapy into your routine, simply getting outdoors into natural light can work too. Here’s a quote from a study titled Light as Therapy for Sleep Disorders and Depression in Older Adults:

In warm climates, half an hour of outdoor daylight exposure each morning would constitute an inexpensive, convenient first-line treatment. When outdoor exposure is impractical, one of the available modalities for indoor light therapy can be prescribed.

What do you need for light therapy?

Before you go ahead and invest in a lightbox for sleep, it’s important to first speak with your doctor about any sleep issues you’re having. They’ll give you more options and tailor your treatment to your specific problem and situation.

However, if you’ve been told your issue is circadian-related and advised to get light glasses from your GP, then it’s good to understand what you should look for.

  • The first thing to look for is the type of light the box emits. The type of light that is most effective for promoting sleep is typically a cool-white or blue-enriched white light with a high colour temperature (around 6,500 Kelvin). This type of light is most similar to natural daylight and is most effective at suppressing the production of the hormone melatonin, which makes you feel sleepy. It is especially important to be exposed to this type of light in the morning or early afternoon to regulate the body’s circadian rhythm and help promote good sleep at night.
  • Make sure to look for a lightbox that filters UV light and has a light intensity of 2000 to 10000 lux.
  • Additionally, make sure the box you choose is not designed for tanning or skin care. The light needed for mood and sleep is different and these are more likely to harm you than help you if you use it in this way.

Lightboxes come in a range of sizes, so it’s important to know where you’re going to perform the therapy. Some are more compact than others, so you’ll want one that suits your own needs. However, if you feel a box is too bulky, opting for light therapy glasses can also have similar effects.

Are there any negative side effects?

There aren’t any serious side effects to using low-intensity light therapy to help you sleep. After all, you’re only exposing yourself to light. However, it is worth noting that some people do experience minor effects.

Healthline states that light therapy can cause side effects such as:

  • Headaches
  • Eye strain
  • Nausea
  • Irritability

Often this can be a sign you’re using a light that’s too bright or you may be sitting too close to your light source. If these effects don’t wear off, see your GP for further assistance.

What else can I do?

We know that light therapy might not be practical if you don’t have access to a lightbox when you need it. Don’t worry, there are other changes you can make to your routine that can support better sleep.

These include:

  • Removing blue light-emitting objects from your room, especially during your bedtime routine.
  • Have a good sleep schedule where you have a set time when you wake up and go to bed.
  • Resist any urge to nap as this can disrupt your schedule.
  • Limit caffeine intake, especially in the evening.
  • Make sure your bed is cool, dark and quiet
  • Avoid alcohol and nicotine before bed.

Get more advice with our top tips for a better night’s sleep.

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