You probably have co-workers who joke about how much coffee they need every morning. But by mid-afternoon, they often fade and have to fight the urge to fall asleep at their desk. And then later that night, when they can finally get some rest, they lie wide awake. Sound familiar?
Sleeping problems are very common for adults. We’ve all felt the short-term effects of a poor night’s sleep, and you’re probably aware of the health risks associated with chronic sleep problems. What many don’t realize is the central role that light plays in our sleep cycle, and additionally, that some types of light are better and worse for healthy sleep.
In this article, we’ll cover the normal types of sleep, the consequences of poor sleep, and how red light therapy can help.
What is Normal Sleep?
Most of us have experienced sleep deprivation at some point. When it comes to your health, chronic sleep problems shouldn’t be taken likely. We’ll cover some of the negative consequences of sleep deprivation, but first, it’s important to understand that not all sleep is the same.
Not All Sleep is Created Equal
A full night’s sleep is made up of a series of 1.5 to 2-hour sleep cycles that include two main phases of sleep. Both are essential to ensure optimal health when we’re awake.
NREM Sleep: NREM stands for “non-rapid eye movement.” Ideally, NREM sleep should make up about 75% of your total sleep. It ranges from light sleep to our deepest, most restorative sleep. Our blood pressure drops, muscles relax, tissue growth and repair takes place, energy is restored, and essential growth hormones are released. 
REM Sleep: REM stands for “rapid eye movement.” This describes the quick eye movements that happen during deep sleep, the only time when you actually dream. REM sleep should represent about 25% of all sleep. It first occurs about 90 minutes after you fall asleep and reoccurs every 90 minutes. 
The Negative Consequences of Poor Sleep
In the short-term, sleep deprivation affects our mood and makes us less alert, so we’re less productive and more likely to make erratic decisions. In the long-term, chronic sleep problems contribute to numerous other physical health issues. Here’s a closer look at the major negative health effects associated with chronic poor sleep:
Being tired every day is no way to get in better shape. Either is sleeping all the time. Epidemiological data suggest a strong correlation between weight gain with either too little or too much sleep. In addition, a large base of clinical evidence shows a strong connection between short sleep cycles and Type II diabetes. 
Sleep deprivation has also been shown to decrease leptin, a vital appetite-suppressing hormone. Leptin acts as a sort of internal fuel gauge, so when it’s thrown off by abnormal sleep patterns, it’s harder to regulate when you need to eat. 
A new study in the journal Biological Psychiatry reports that inflammatory markers were found in people who have sleep disturbance issues as well as overly long sleep durations. This highlights the fact that both too little and too much sleep may cause inflammation. 
Cytokines, small proteins that promote normal inflammatory responses, help regulate sleep, health, and physiological functions such as cognition, mood, performance, and fatigue. Not surprisingly, these pro-inflammatory cytokines are negatively impacted by sleep deprivation. 
We’re only beginning to understand the long-term cognitive effects of insufficient sleep. There’s a general consensus among experts that lack of sleep leads to slower response times, decreased alertness, and an increased variability in performance.
Recent research suggests sleep deprivation may especially affect cognitive functions that rely on emotional data, which makes sense to anyone who’s been tired, cranky and made impulsive decisions they later regret due to a lack of sleep. 
How Light Impacts Your Sleep
Light plays a major role in your sleep cycle, more than most of us realize. The body’s circadian clock interprets light as a sign of when to sleep and be awake, which regulates everything from appetite and metabolism, to hormone levels and immune function.  Of course, this all developed long before humans figured out how to make light available at all hours of the day. We have incredible lighting technology now, but our bodies still react to light like they always have.
How Blue Light Keeps You Up at Night
Not all light is the same, and some kinds are a lot better than others for sleep. Based on the graph above, you can see that blue light has a high color temperature, so our body reacts to it like bright daytime sunlight. Most of our electronic devices have screens that emanate blue light, and when you sit in front of a glowing screen for hours, your body gets the message it’s time to be wide awake. When you jump in bed and try to fall asleep right after, it’s difficult for your body to adjust, even if you’ve been tired all day. This article goes deeper into the consequences of excess blue light exposure if you want to know more.
Red Before Bed
Red light is ideal for evenings and after dark because it has a low color temperature, far lower than regular sunlight. You can be in red light at night without giving your body a jolt and altering your internal clock. If you’re having trouble sleeping and you’re surrounding yourself with unnatural blue light every night, that could be a big factor. Switching to natural red light in the evenings can help your body ease into its sleep cycle more naturally.
Red light therapy has been studied closely and found to improve sleep quality as well. In one study performed among elite women basketball players, the participants tried 14-30 minute light therapy sessions once a night for 14 nights. The short-term results showed improved sleep and the researchers found red light therapy to be a nonpharmacologic and noninvasive therapy for treating sleep disorders. 
Melatonin: If you’ve had trouble sleeping, you might have tried melatonin. It’s a naturally-occurring hormone that regulates sleep and wakefulness. Exposure to light after dark inhibits the body’s ability to release melatonin, increasing the time it takes you to fall asleep and preventing you from staying asleep. If you’re in red light before bed, you’ll produce more melatonin than if you’re surrounded by synthetic blue light. 
In a study with 47 people with TBI (traumatic brain injury), patients received 18 red/near infrared light treatments and saw an average increase of 1 hour of sleep per night. Researchers concluded that red and near infrared photons increased melatonin levels in participants. 
Conclusion: Get Better Sleep with Red Light at Night
It’s no secret that poor sleep and the resulting fatigue makes us less healthy and less productive in the short and long term. What fewer people realize is that the light we’re exposed to plays a huge role in our ability to sleep. Red light therapy has been found in numerous studies to promote better sleep, and there’s a huge base of research showing that 7-8 hours a night for adults is not just a luxury, but a must for people seeking optimal performance and recovery. 
Scientific Sources & References:
 Harvey C., Bruce A. “Sleep Disorders and Sleep Deprivation” National Academy of Sciences. 2006, Bookshelf ID: NBK19960. doi: 10.17226/11617
 Kristen K. “Impact of sleep and sleep loss on glucose homeostasis and appetite” Sleep Medicine Clinics. 2007, June; 2(2): 187-197. doi: 10.1016/jsmc.2007.03.004
 Sunil S., Mani K. “Sleep and Metabolism: An Overview” Int J Endocrinol. 2010, Aug 2. doi: 10.1155/2010/270832
 Michael I., Richard O., Judith Carroll. “Sleep Disturbance, Sleep Duration, and Inflammation: A Systematic Review and Meta-Analysis of Cohort Studies and Experimental Sleep Deprivation” Biological Psychiatry. 2016, July 1; 80(1): 40-52. doi: 10.1016/j.biopsych.2015.05.014
 Janet M., Norah S., Hans M., Monika H. “Sleep Loss and Inflammation” Best Practice & Research Clinical Endocrinology & Metabolism. 2010, October; 24(5): 775-784. dio: 10.1016/jbeem.2010.08.014
 Killgore WD. “Effects of sleep deprivation on cognition” Progress in Brain Research. 2010; 185: 105-129. doi: 10.1016/B978-0-444-53702-7.00007-5
 Lirong Z., Phyllis Z. “Circadian Rhythm Sleep Disorders” Neurologic Clinics. 2012, November; 30(4):1167-1191. doi: 10.1016/j.ncl.2012.08.011
 Zhao J., Tian Y., Nie J., Xu J., Liu D. “Red light and the sleep quality and endurance performance of Chinese female basketball players” Journal of Athletic Training. 2012, November-December; 47(6):673-678. doi: 10.4085/1062-47.6.08
 Morita T., Tokura H. “ Effects of lights of different color temperature on the nocturnal changes in core temperature and melatonin in humans” Journal of Physiological Anthropology. 1996, September; 15(5):243-246.
 Margaret N., Michael H. “Traumatic Brain Injury: A Major Medical Problem That Could Be Treated Using Transcranial, Red/Near-Infrared LED Photobiomodulation” Photomedicine and Laser Surgery. 2015, September; 33(9): 443-446. doi: 10.1089/pho.2015.3986
 Nathaniel W., Safwan B., Gregory B., Donald B., Orfeu B., Daniel B., David D., James G., Michael G., Clete K., Raman M., Jennifer M., Sanjay P., Stuart Q., Esra T. “Recommended Amount of Sleep for a Healthy Adult: A joint Consensus Statement of the American Academy of Sleep Medicine and Sleep Research Society” Sleep. 2015, June; 38(6): 843-844. doi: 10.5665/sleep.4716