Can Red Light Help You Sleep?

What keeps you awake at night? 

Is it tomorrow's endless 'to-do' list, a lingering conversation from yesterday, the stress of not being able to fall or stay asleep, or something else you just can’t put your finger on? 

A minimum of 7 hours of sleep is necessary for proper cognitive and behavioral function [10], yet 70% of adults report sleeping less than 8 hours per night during the week, with some even dipping below 6 hours [11]. If you're considering weekend sleep catch-up as a solution, think again. Scientific findings suggest that our health never fully recovers from the impacts of lost sleep [43].

 

Why Is Sleep So Important?  

Sleep isn't just a luxury; it's a necessary process that helps us:

• Learn and process new information - this is why all-nighters might backfire when studying for exams. After a day of processing and engagement, the brain has been hard at work, especially since there is no end to stimulation with our access to smartphones and social media. When you fall asleep, your brain has a chance to clear out the cobwebs and remove toxic waste that builds up throughout the day [1, 2]. Sleep rests the brain, setting the stage for learning and memory [3].

• Rejuvenate and repair tissue - ever heard of the phrase “beauty sleep” - there is truth in that! Did you know that certain hormones like growth hormone (important for tissue repair) and testosterone are released during deep sleep? Growth hormone helps our tissues repair and stay healthy, and testosterone is important in both men AND women for overall health. 

• Detoxify - did you know that your brain takes out toxins via the ‘glymphatic system’ while you sleep? Studies have shown that when we don’t get enough sleep, these toxins can accumulate [4, 11]. 

• Maintain metabolic health - ever notice sugar cravings becoming more intense after a poor night’s sleep? Studies have shown that sleep deprivation can affect our metabolism, throwing off blood sugar control and contributing to weight gain and inflammation. 

So, as you can see, sleep is an important pillar of health worth doubling down on.

 

Without sleep…

… our mood, productivity, and long term health are dramatically impacted. 

While you may think skipping sleep for a night or two might not seem like too big of a deal, repeated lack of sleep can induce chronic insomnia symptoms like fatigue, cognitive decline, restricted attention and learning [12], and poor mood.

Moreover, inadequate sleep can disrupt our metabolism, leading to weight management issues, trigger inflammation [13, 14], and pose risks for anxiety, and depression.

 

The 5 Root Causes Of Poor Sleep

It can be extremely frustrating to toss and turn, unable to drift off - especially knowing how critical sleep is for our health. 

Typically, sleep difficulties at night can be traced back to these 5 biological factors:

• Light
• Food
• Exercise 
• Social activity
• Stress

Many people are making common mistakes around these factors and eroding their sleep. 

Consider modern-day living: inadequate sunlight exposure during the day coupled with excessive artificial lighting at night, along with late dinners and stress. No wonder 1 in 3 Americans sleep less than the recommended 7 hours per night [9]! So, if you find it difficult to fall asleep or stay asleep, you are not alone. We feel you!

Read on as we share tips on how to improve your sleep - we have a special secret involving one of the critical factors mentioned above…

 

The Master Key To Sleep: The Circadian Rhythm

Answer these 3 questions:

• Do you have trouble getting up in the morning?
• Do you have trouble focusing during the day?
• Do you ever doze off during the day?

If you answered 'yes' to any of these, you might be experiencing signs of a shift in your circadian rhythm - aka our internal body clock. This can lead to various symptoms like feeling tired, low in mood, a drop in physical performance, and even digestive and blood sugar issues.

Understanding your circadian rhythm is key here.

The circadian rhythm operates on a near 24-hour cycle, synced to the Earth's rotation. This clock helps schedule the release of certain hormones at the right times: for example, cortisol from our adrenal glands to wake us up, and melatonin, known as the sleep hormone, from our pineal glands to help us fall asleep.

It doesn’t just stop at sleep though - pretty much all internal events in our body are affected by the circadian system, including hormone secretion, temperature regulation, digestion [16] and activity in the microbiome, cognitive function, metabolism, muscle performance, and recovery. 

You might be interested to learn that the same meal, with the same calories and macronutrients, eaten at different times of day can have very different effects on our blood sugar (and therefore weight gain) [15] - this is down to circadian rhythm! Amazingly, the TIME of day food is consumed matters…  

 

How Does Light Impact Our Circadian Rhythm? 

Light has a MASSIVE impact on our circadian rhythms (our body's internal clock). If you don't receive light exposure at the appropriate times, it's likely that your internal clock will become disrupted, consequently affecting your sleep.

4 Things That Determine Light’s Impact On The Body Clock:

• Timing - be sure to get light at the right times 

The timing of light exposure over the course of the day can alter when we feel most alert or sleepy. Light exposure in the evening inhibits melatonin production [18] so your body thinks it’s not time to sleep yet and will push back your natural sleep time.

If you’re exposed to light as soon as you wake up, this shuts off melatonin production, setting up your body clock to sleep at the right time. This is why you’ve probably heard many experts talking about the importance of getting 10-30 minutes of morning light exposure upon waking. It’s to keep your internal clock synced with the sun!

• Color - get the right TYPE of light 

Some colors have stronger effects on our circadian rhythm than others, because of their shorter wavelength. Here are some wavelengths for common colors:

• Blue (~470 nm)
• Green (~550 nm) 
• Amber (~590 nm)
• Red (~660 nm) 
• Visible light includes all light in this range (380-700 nm)

Blue light has the strongest effect on our circadian rhythm [20]. Exposure to blue light at the wrong times can stop our body from producing melatonin and throw our metabolism off track [5]. It's like tricking our bodies into thinking it's daytime when it's actually time to sleep!

• Intensity 

A brief exposure to very bright light before bed can suppress melatonin as effectively as longer exposure to dim light, resulting in a delayed feeling of sleepiness [19].

Normal room lighting (200 lux intensity) is bright enough to suppress melatonin [44]. For context, a phone screen is usually 500-800 lux - if you’re reaching for your phone for just one quick message, it may have a greater impact on your sleep than you think! 

• Duration 

In addition to the intensity of light, the longer we’re exposed to light, the more it shifts our natural bed time, especially if we’re exposed in the evening. We weren’t designed to be in the presence of light for longer than the natural sun course! 

 

But How About Red Light? 

When it comes to sleep, blue light = bad. Red light = rest!

Darkness is what triggers the pineal gland (in our brains) to secrete melatonin, our sleepy hormone. 

It turns out that red light may trigger the production of melatonin in areas outside of the pineal gland. 

This is exciting because we usually think of melatonin as coming only from the pineal gland. Red light could be unlocking extra sources of this sleep-inducing hormone that also has anti-inflammatory properties to boot…

Here’s the science: 

• In a study on 20 female athletes, the China Institute of Sport Science found that “red light may positively affect sleep quality and endurance performance.” Participants lay on a whole-body red-light treatment machine (average wavelength 658 nm) for 30 minutes before bed for 2 weeks, and were assessed using the Pittsburgh Sleep Quality Index (PSQI) questionnaire. The group receiving red-light treatment experienced improved sleep (demonstrated by greater improvement in global PSQI scores) and an increase in melatonin levels, as well as a 13% increase in athletic performance [26].
• It has been suggested that 600–1000 nm (red - infrared) wavelengths promote the release of melatonin in animals [27]. Further, red light therapy using LED has been reported to induce sleep and prolong sleep duration in mice. The pigment in the eyes that detects light was found to be more sensitive to blue light and less sensitive to red light. This means that even a little bit of blue light can mess with sleep quality, but red light doesn't have this problem unless it's really bright (above 10 lux). In fact, at a brightness of 20 lux or more, red light actually helps to promote sleep [28]. 

Red light may also help us rest by targeting other sleep-promoting pathways, separate from melatonin regulation.

 

A Solution For Stress-Induced Sleep Challenges

Many people experience stress without even realizing it, making it an invisible yet potent factor that erodes our sleep. Addressing stress can have positive impacts on sleep, and this is where red light therapy can play a significant role: 

• Stress affects sleep, leading to difficulties falling asleep, and staying asleep [33]. Red light is great for regulating key hormones like cortisol (stress), serotonin (“feel-good” chemicals), and nitric oxide (linked with inflammation [34] - a product of high stress levels). 
• Trials on mice have shown that light therapy treatments using 810 nm laser (this is light in the near-infrared range) decrease cortisol levels by mediating oxidative stress, reducing inflammation, and improving brain function [35, 36], which could have potential benefits for improving restful states.
• In a 2016 study on rats, researchers measured the effect of red (630 nm) and NIR (810nm) on stress. The study indicated that “treatments decreased both cortisol and blood glucose levels” [37], suggesting that RLT can help support a healthy stress response. 
  

 

Common Sleep Aids

There are many sleep aids on the market including sleeping pills and melatonin supplements, which are highly variable and of course you should always discuss with your doctor before use because we really don’t know the long term consequences of supplementing with these and whether it could start to disrupt our innate melatonin production. Sedatives may be helpful in the short term but benzodiazepines (e.g. Xanax, Valium) have been associated with impaired cognitive function in the long run.

 

Using Light To Your Advantage

If you're struggling with sleep, a straightforward first step is to adjust when and how long you're exposed to light, its brightness, and its color. The following steps can help reset your internal body clock:

1. Expose yourself to natural light within the first 30 minutes of waking.

2. Soak in some natural sunlight around midday to keep your clock in check! If you must use artificial lighting in the evening, you can reduce the impacts of this by soaking up as much daylight as possible [40].

3. Use red or amber light before bed to wind down. It helps mimic the effect of sunset, since going directly from bright light to darkness can prevent the brain and body from falling asleep [23].
Try using LUMEBOX as mood lighting after dinner (place it facing a wall so you’re not looking directly at the light)!

4. Limit blue light exposure 2 hours before bed since this interferes with melatonin. If you absolutely must use a device, try blue light blockers, or night mode. 
BE AWARE that night mode does not reduce the intensity of the light! It only changes the color of the screen (less blue light). Therefore, it’s also important to use the lowest brightness setting on your device.
Need more phone hacks? Check out our Instagram reel @lumeboxpro to learn how to change your phone screen to red and limit blue light exposure!

5. Include red light therapy 1-2 hours before bedtime to relax. We at LUMEBOX like using either NIR alone or RED+NIR at the back of our neck/upper back, while we do 10 minutes of meditation before bed.

6. Keep your bedroom dark.

7. If you need to use the bathroom during the night, avoid turning on bright lights or using your phone. Instead, use red or amber night lights.

8. Keep a regular schedule. Wake up as close to the same time as you can every day, and don’t fight the sleepiness when it gets nearer to bed time!

 

Won't The Red Light Before Bed Keep Me Awake? 

Tests have revealed that red light treatment does not significantly alter any sleep measurements [38].

In a study on both males and females experiencing sleep disturbance, participants were treated with 2 hours of evening exposure with either bright white light or dim red light for 12 days. Results from sleep and circadian rhythm recordings show that the bright light (~4000 lux) resulted in substantial changes in sleep quality and a phase delay of 3 hours, whereas the red light (50 lux) only induced a phase delay of 8 minutes [38]. 

So it seems red light has less impact on sleep, as long as it is not too bright. Wear your goggles if you’re concerned!

Everyone is different though - we have found that some people find red light therapy stimulating whereas some find it relaxing and sleep-promoting. It’s worth experimenting to find how it impacts you as an individual. 

 

What Else Can I Do? 

Light is POWERFUL when it comes to the circadian rhythm, BUT it is not the only thing that impacts our sleep… 

To improve sleep quality and quantity, and to support our circadian rhythm, consider these tips related to other key factors: eating, physical activity, social interaction, and stress management. ⬇️

Eating 

• Try to eat your last meal 2-3 hours before bedtime [41], and eat around the same time every day.
• Reduce alcohol and caffeine, and avoid late at night.

Physical activity

• Exercise earlier in the day. If you exercise too close to bed your muscles can’t relax and it will hinder your ability to fall and stay asleep [39].
• Try magnesium before bed (200-350 mg for women). Make sure to check with your doctor before taking any supplements. 
• Use LUMEBOX on your muscles for relaxation [8]. The combination of RED and NIR light is effective in soothing lymphatic vessels, aiding in the removal of toxins from body tissues [4, 6, 7]!

Social interaction and Stress

• Put away the social media (stimulation from the content could keep us awake even longer than the blue light can!)
• Create a bed time routine to help signal to the brain that it’s time to wind down. Try a relaxing warm bath, a daily journal reflection, or a cup of hot chamomile tea. 

Optimize your sleep environment! 

• A cool room will help you fall asleep faster, since the core body temperature needs to drop 1-3°C to fall asleep [42]. The optimal temperature is 60-68°F (15.6 - 20°C). 
• Keep it quiet and calm

Here’s to restful nights and brighter days!

 

Medical Disclaimer: The information contained in this blog post is intended for educational purposes only and should not be used as medical advice. Everyone responds to light differently. Testimonials are not a guarantee of the results you or anyone who uses LUMEBOX will get because your success depends entirely on your circumstances, and the studies on red light therapy shared were not specifically performed using LUMEBOX. Please check with your doctor before using red light therapy and do not change your medical treatments or lifestyle without consulting your physician first. 

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