Table of Contents
- Sleep Cycles
- Circadian Rhythm
- Sleep Disturbances
- Does Red Light Therapy Help Sleep?
- How Does Red Light Therapy Promote Sleep
- Quick Tips to Getting Better Sleep
Red light therapy leverages unique properties of certain wavelengths of red (visible) and near-infrared (invisible) light to help promote wellness. People use red light therapy for a variety of purposes, including to reverse skin aging, improve wound healing, increase energy levels, reduce inflammation, improve joint health, and have better sleep.
The way red light therapy works is still an area of ongoing research. Many studies have shown that red light therapy has various potential benefits and that the use of red light therapy can be a safe and painless way to achieve health benefits.
The simple presence of light has been known to affect our biology in a variety of ways. Sleep hormones are regulated by the amount of light entering our eyes. Light affects how much pigmentation our skin produces. Certain wavelengths of light also stimulate our body to make vitamin D. Light is used to break down a chemical called bilirubin in some newborns and is used for this purpose in hospitals around the world. High-energy light can also be used to kill bacteria and disinfect surfaces.
Red light therapy uses specific wavelengths of light that are longer than other colors of light. Red light and near-infrared light can penetrate deeper into body tissues than other visible wavelengths of light and reach tissues that these other wavelengths will not.
One interesting application of red light therapy is as a method to improve sleep. Red light therapy has been used to help promote sleep for many years, but it is only recently that research has started to explore what kind of benefits red light therapy provides and how it works to promote sleep.
Sleep is a vital part of health. We often do not consider the implications of sleep, but most people spend more time sleeping throughout their lives than any other activity. People who consistently sleep the recommended eight hours a night will spend one-third of their lives asleep.
Despite the high importance of sleep, the exact biological purpose it serves is still a medical mystery. Sleep has been shown to form and maintain neurological pathways in your brain, allowing you to think more clearly, concentrate better, and have better memory abilities. Sleep has also been shown to remove toxins that accumulate in your brain during the day.
There are two basic types of sleep that everyone has. These two types of sleep occur in cycles and include rapid eye movement (REM) sleep and non-REM sleep.
Non-REM sleep occurs in three stages:
- Stage 1: This stage of sleep is the transition from wakefulness into sleep. Brain waves begin to transition from an active stage into a slower sleep state.
- Stage 2: During the second stage of sleep, your brain waves slow even more. Your eyes stop moving, your heart rate and breathing slow, and your body temperature decreases.
- Stage 3: Brain waves become even slower in the deepest stage of sleep. Your body becomes very relaxed, and it would be difficult to wake up in this stage. This stage of sleep plays a large role in helping you to feel refreshed in the morning.
REM sleep occurs periodically while you are sleeping between the stages of non-REM sleep. Longer and deeper periods of REM sleep occur the longer that you sleep. REM sleep is the stage of sleep in which dreams occur. REM sleep happens more frequently as morning approaches and is the closest form of sleep to wakefulness.
The circadian rhythm is the overall cycle that your body goes through in roughly a 24-hour period. While there are many important biological functions that the circadian rhythm influences, sleep is one of the most important. The circadian rhythm synchronizes to light, encouraging sleep when light levels fall.
The impact of light on the circadian rhythm is well established, and science has proven that exposure to light immediately before going to bed can disrupt sleep. Recently, it has become better understood that the wavelength of light plays an essential role in influencing this. Blue light, which has a higher energy and shorter wavelength, has been shown to suppress melatonin, a hormone that the circadian rhythm uses to promote sleep.
The negative effects of blue light on sleep are so impactful that smartphone makers have recently begun providing settings that can automatically reduce the amount of the blue, high energy light that your phone generates. People use these settings to reduce exposure to high-energy light at night and to sleep more soundly.
While sleep is regenerative and essential to good health, sleep disturbances can have a profound negative effect. Chronic lack of sleep has been connected to many health problems, including:
- High blood pressure
- Heart disease
People who struggle to get to sleep or have chronic sleep problems have a higher risk of disease when compared to those who sleep well and may have long-term health problems that could otherwise be avoided.
Does Red Light Therapy Help Sleep?
Red light therapy uses specific wavelengths of red and NIR light to help rejuvenate cells and promote overall health. One of the popular uses of red light therapy is to help people have better sleep quality.
While the use of red light therapy to promote sleep health is a newer technology, there are several studies that have shown benefits to using red light therapy. One of the first studies to examine this use of red light therapy technology examined the impact that it had on a group of elite female basketball players. In this study, the players were divided into two groups. One group was not given any red light therapy, while the other group was given full-body red light therapy for 30 minutes every night for two weeks.
The researchers then evaluated the athletic performance of the two groups, the quality of their sleep, and the levels of melatonin in their blood. Researchers found that the physical endurance of the group that received red-light therapy had improved more than the group that had not. The group that received the red light therapy also reported that the quality of their sleep improved after two weeks of therapy. The levels of melatonin in the blood of those who received the red light therapy were also significantly higher than those who did not receive the red light therapy.
In addition to multiple small studies showing that red light therapy has positive effects on sleep quality, many people anecdotally report that the use of red light therapy helps them sleep better and feel more refreshed after waking up.
While there have been several small studies that show promise in this area, scientists have not yet performed any of the large-scale studies needed to conclusively prove the benefits of red light therapy for sleep. However, even though a large-scale study has not yet been run, the early indicators that smaller studies and anecdotal evidence provide show meaningful benefits and that a larger study would likely show widespread positive sleep benefits from red light therapy.
How Does Red Light Therapy Promote Sleep
While early studies on red light therapy show that it helps to promote better sleep, the question of how this occurs is one that scientists are only starting to address.
A group of researchers, led by research scientist Dr. Ronnie Yeager, published an important paper outlining their scientific hypothesis for how red light therapy improves sleep. This hypothesis hinges on the hormone melatonin. Melatonin plays a crucial role in regulating the circadian rhythm and encouraging sleep. Blue light has been shown to suppress melatonin levels, which is the primary reason blue light encourages wakefulness.
The researchers provided insights into how red light therapy could interact with cells, increasing melatonin levels. They also elucidated potential mechanisms explaining how the interaction of red light wavelengths of light interacting with melatonin could also explain some of the other health benefits of red light that had previously not been well understood.
If the hypothesis provided by these researchers is correct, by stimulating melatonin, red light therapy could encourage the initiation of sleep and help sleep to be more sustained once you get to sleep. While further research is needed to verify this initial model, the foundational concepts of this research intuitively explain how red light therapy would effectively promote sleep.
Quick Tips to Getting Better Sleep
So how do we pull this all together into some practical actions you can take to get better sleep?
Here are some suggestions:
1) Start the day off by immediately going outside in the sun to 'reboot' your circadian clock. Early morning sun exposure has been shown to improve sleep.
2) If possible, get outside in the sun periodically throughout the day. As discussed in this paper from Oxford, the quality and architecture of sleep is associated with preceding light exposure.
3) Try using a Mito Red Light device around sunset (with eyes properly shielded) for 8-10 minutes to support natural melatonin levels.
4) Reduce bright ambient light in the evenings by opting for some amber/orange/red bulbs.
5) Further avoid blue/green light in the evening by wearing blue-blocking glasses.
7) Use black-out curtains to reduce 'light pollution' in the bedroom from outside sources.
These simple tips should help you to easily leverage your light environment to work WITH your biology to promote better sleep!