Sleep is critical. It's a time for your mind and body to rest, recharge, and prepare you for the following day, alert and refreshed. But not everyone gets enough slumber or quality kip. So, can red light therapy for sleep be the answer, and how does it work [1]?
Red light wavelengths stimulate the production of the naturally occurring hormone melatonin. The human brain does this anyway as darkness falls. But studies show that red light therapy (RLT) improves melatonin levels and sleep quality. Researchers also found that red and ambient white light together enhanced circadian rhythm [2].
RLT is gentle, non-invasive, and affordable. This article looks at the ways people use it to help them sleep. For many, it's the perfect, safer alternative to medications, without the risk of addiction or nasty side effects. But, first, let's look at the importance of sleep and its connection with your health and wellbeing.
Why You Might Need RLT for Better Sleep
Most people who don't get enough sleep or quality slumber have disruption to their 24-hour body clock. This 24-hour cycle is your circadian rhythm. If your body clock gets out of whack, you could be feeling tired at all the wrong times. For example, you're sleepy when you should be awake and alert when you should be sleeping.Â
RLT can help to reset your body clock and restore your circadian rhythm.
Research 2019: A study in Nature & Science of Sleep found a positive link between red-light exposure and decreased sleep inertia... the groggy feeling experienced upon awakening [3].
Red Light Therapy by Other NamesÂ
RLT is known by a few names, which is confusing to those trying to learn about it. Thus, our guide only uses RLT or red light therapy and NIR (near-infrared light).
The table below shows the other names you want to note for future reference:
 FULL NAME | ABBR |
 Soft Laser Therapy | SLT |
 Photonic Simulation | - |
 Photobiostimulation | - |
 Photobiomodulation | PBM |
 Low Power Laser Therapy | LPLT |
 Low Level Light Therapy | LLLT |
 Cold Laser Therapy | CLT |
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The Link Between Light and Sleep, Night and Day

Light influences your circadian rhythm. It's a process that begins in a part of your brain that's home to nerve cells called the hypothalamus. Within your hypothalamus is a cluster of cells known as the suprachiasmatic nucleus (SCN). SCN processes light signals as they enter your eyes so that your brain can determine night from day.
The low colour temperature of the red light helps you relax. It has a calming influence on your mind, unlike blue light, which has the opposite effect.
Melatonin's Role in Your Sleep Cycle
You learned in the introduction that melatonin is your sleep hormone. Your body starts to produce it after sunset or in the early evening as you wind down. However, bright lights—and especially blue light—can disrupt the production of melatonin. We'll look at ways to reduce your blue light exposure shortly.
Red Light Therapy is a friend of melatonin, encouraging more production than average.Â
Cortisol's Role in Your Sleep Cycle
Cortisol is melatonin's counterpart. Its job is to help you wake up in the morning and stay alert throughout those conscious hours of the day. However, your cortisol levels start to wane during the latter part of the day. It does this to allow sleep hormones, i.e., adenosine and melatonin, to take over and prepare your body for rest.
Here are the eight processes a healthy body goes through during a good night's sleep:Â
- The brain sorts then process the information from the conscious day
- Hormones, all with different purposes, start to flood the body
- Your flight or fight sympathetic nervous system begins to relax
- Cortisol (the stress hormone) levels drop in the early hours of sleep
- Muscles temporarily paralyse during the NREM and REM dream stage
- Anti-diuretic hormone or ADH switches off to reduce the need to pee
- Your immune system releases small healing proteins called cytokines
- Cortisol levels rise and peak soon after awakening
There's a bit more going on than this. Still, the procedures above offer a good snapshot of a quality slumber cycle.
Reasons You Can't Drift off or Stay Asleep
There's no single answer to why you can't sleep or sleep well. It could be underlying health conditions, bad habits, busy schedules, or a poor bedroom environment. Or, you may simply be stressed about not sleeping. Sleep-related disorders, e.g., REM sleep behaviour disorder, restless legs syndrome, and apnoea, are other culprits [4].
What Happens When You Don't Sleep Well?

Daytime tiredness is horrible when you have no opportunity to grab a power nap. And when sleep deprivation is chronic (long-term), it becomes a health issue, too. Medications may help in the short term. But they can produce potentially harmful side effects in the longer term, but RLT doesn't [5] [6].
Here are the main reasons why everyone should take sleep deprivation seriously:
- Higher risk of heart disease and stroke
- Contributes to high blood pressureÂ
- Weaker immune system
- Leads to weight gain, including obesity
- Mental health disorders, e.g., anxiety, and depression, etc.
- Trouble concentrating for extended periodsÂ
- Drop in academic and work-related performanceÂ
- Premature aging
Sleep benefits the brain and body, including all internal organs. In short, it protects and maintains your immune system, enabling you to live an efficient and healthy life [7]  .
Did you know: Sleep deprivation is not unique to humans. Your pets and even insects can experience insomnia as well, say researchers [8] [9].
Now let's look at how your sleep issues might benefit from RLT treatments.
Treating Sleep with Infrared Light

Treating sleep disorders is just one of the many benefits of RLT. Light treatment is growing in popularity for several reasons. For one, it has a pretty low operating cost, but its biggest appeal is that it's a safer alternative to traditional medicine.
Red Vs Blue Light
A little knowledge of red and blue light makes it easier to understand how light affects sleep. But what is blue light, why is it bad for rest, and how can you avoid it?
The Problem with Blue LightAll modern gadgets with screens emit blue light. That includes smartphones, tablets, flat-screen TVs, computer monitors, and even compact fluorescent lamps. Too much exposure to any of the above close to bedtime can make it hard to fall asleep. Either that or you have trouble staying in slumber after you doze off.Â
Blue light sucks as it obstructs your body's production of the sleep hormone melatonin before bedtime. It can even trigger painful headaches in some people. The way to avoid it is not to expose your eyes near bedtime to devices that emit blue light [10].
Why Red Light Triumphs
RLT treatments supplement a lack of light exposure from the sun. A new generation of home devices delivers red and near-infrared (NIR) light directly to your skin, supercharging the cells. Red light intake is a critical factor in quality kip and circadian rhythm. It's why so many problematic sleepers are now turning to RLT.
Not All Red Light Is Equal
People spend way too much time indoors these days, depriving their bodies of that much-needed outdoor natural light source. Those bright artificial indoor lights are no substitute, either. On the contrary, extended exposure to artificial light can disrupt your circadian rhythm and mess with your sleep cycle [11] [12].
The type of light that supports better sleep emits a red-light wavelength. Thus, a red-tinted light build will have no physical therapeutic effect at all. It may create a relaxing ambience that some may find comforting. But regular coloured bulbs cannot emit the red-light wavelengths needed to enhance sleep.Â
Summing Up
You may have heard that vitamin supplements are no substitute for nutritious food. Instead, they supplement a diet and add to its overall nutritional profile. Well, red light therapy is the same. Yes, it can enhance your sleep quality. But ideally, you should use it in conjunction with—not instead of—other best practices and bedtime routines.
Resource Links
- https://medlineplus.gov/ency/importance-of-sleep/Â
- https://journals.sagepub.com/red-and ambient-white-light/Â
- https://www.ncbi.nlm.nih.gov/sleep-inertia/Â
- https://www.sleepfoundation.org/insomnia/what-causes-insomnia/Â
- https://www.webmd.com/side-effects-of-sleeping-pills/Â
- https://www.medicalnewstoday.com/RLT-no-risk-of-side-effects/Â
- https://www.ncbi.nlm.nih.gov/sleep-and-immune-systems/Â
- https://www.nationalgeographic.com/insects-insomnia/
- https://www.petmd.com/dog/general-health/my-dog-getting-enough-sleep/Â Â
- https://www.webmd.com/sleep-disorders/sleep-blue-light/Â
- https://ec.europa.eu/health/artificial-light/Â
- https://www.sleep.org/how-artificial-lights-affect-sleep/Â