Spring has finally arrived and in Alaska that means not just warmer days, but longer more light filled days! Yeah! I am a huge fan of more sunshine! It’s easy to take the rising of the sun and its presence in our daily lives for granted because most of us have never experienced anything other than that predictable rhythm. Many scientists would argue that the sun is the single most important piece of our physical world; that without it, all life on earth would literally cease to exist. The sun provides the entire planet with not only the energy required to sustain life, but its warmth, radiation and light influence our atmosphere, climate and weather patterns. As far as impacts of sun exposure on human health, our culture has mostly focused on the potential harm caused by too much UV radiation (UVR). There are also very powerful positive impacts on our health due to appropriate and sufficient exposure to sunlight. That is a topic for another article. What I want to focus on in this writing is the impact light has on your sleep. Sleep quality and quantity is a foundational determinant of health. A healthy home is a home that is designed to support your ability to sleep and sleep well.
I’m going to give you a very simplistic overview of how light exposure impacts sleep and just 10 basic rules you can follow to make sure your home’s sleep environment encourages good sleep.
We have very photo-sensitive cells in the retina of the eye and even in our skin that send signals to our brain that help set our circadian rhythms. A Circadian rhythm is roughly defined as a 24 hour cycle that regulates the physiological processes of most living organisms – including humans. These processes are all encompassing in that they manifest in physical, mental, emotional and behavioral ways. In fact the impact of our circadian rhythm on our health and the ways it can be altered are so complex that a whole field of study, called chronobiology, is devoted to just the study of circadian rhythms. Disorders of the circadian rhythm have been linked to serious disease states and most notably sleep disruption. Circadian rhythms vary with our age too – which is one reason teenagers actually are more naturally inclined to function well later and should be allowed to start their day (and school) later in the morning. Circadian rhythms are known to most strongly respond to light and dark exposure. The most basic way to explain the influence of light exposure on sleep is that when light hits the photosensitive cells of the retina, it signals areas of the brain, many of which are housed in the hypothalamus. The hypothalamus can be thought of as a “gate keeper” of sorts, releasing and inhibiting its own hormones, neurotransmitters, etc. as well as signaling other parts of the brain in order to maintain homeostasis or balance of body functions. It essentially is the connection between the endocrine and nervous system. Anyway, the light signal causes a rise in body temperature, raises the release of the hormones like cortisol and histamine as well as the neurotransmitters that stimulate arousal. It conversely inhibits the part of the brain that house and release melatonin, the hormone primarily responsible for inducing sleep. Sunlight also stimulates the release of serotonin, a mood enhancing neurotransmitter, which is why periods of darkness seem to be associated with a type of depression known as SAD (seasonal affective disorder).
This is a condition many Alaskans likely experience to some degree, even if they are not fully aware of it. In addition, serotonin is a pre-cursor for melatonin. Are you beginning to see how the rhythm of light and dark exposure feeds the cycle of wakefulness and sleep?
In addition to circadian rhythms the body has a sleep-wake homeostasis mechanism that seems to be related to a build up of chemical signals such as adenosine and pressure in the cerebral spinal fluid that can only be relieved by actual sleep. This is why despite stimulants the body eventually forces itself to sleep. Interestingly, light exposure seems to influence this mechanism of sleep regulation too. While many people think they can “get by” on little sleep, the body is designed to thrive on a continuous cycle of about 16 hours of wakefulness followed by about 8 hours of uninterrupted sleep. Lack of sleep eventually catches up to you. There is so much evidence in the medical research that verifies this to be true. One example is that we know melatonin has been shown to be important in supporting the immune system (including suppressing auto-immunity, cancer and inflammation). Lack of sleep is linked to increased rates of diabetes, obesity, cognitive impairment, mood disorders and more. Adequate sleep on an appropriate cycle keeps the body healthy both short and long term.
So what to do for better sleep? Here are just 10 basic rules for a better sleep environment:
Make sure to expose yourself to bright sun light first thing in the morning and throughout the day. Ideally, you want to get up with the sun. Daylight exposure only from a window is likely not sufficient. Make sure to get outside and let the sun hit your eyes and skin. Consider a light therapy devise if necessary. These vary greatly, so ask your physician for their recommendation for a safe and effective type.
Get to bed early as well. Start a ritual of moving toward relaxation about 2 hours before bed. The body is known to get the most restorative work done while sleeping between 10pm and 2am. So, be in bed and asleep in time to hit that natural cycle if possible.
Your bedroom should be clean and clutter free with a good mattress and pillows that are non-toxic and supportive of good sleep posture.
Your bedroom should be used only for sleep and sex. It is not for entertainment like television or for work.
Do not sleep with your phone near your bed. Electromagnetic fields disrupt sleep.
The temperature of the room should be cool – the average is about 65 °F
A fully dark room is critical – install black out shades or curtains that cover even the edges of windows- no nightlights, no lighted clocks, cover LED lights from electronics, literally have no light at all in the room while sleeping. Studies have shown that even your skin has light receptors that can be influenced by any light, artificial or natural, when trying to sleep….even if you think it isn’t bothering you, the chemistry of your body proves otherwise. It’s not enough to simply cover your eyes.
Keep earplugs by the bed and use them if it is safe for you to do so.
Discontinue all exposure to blue-light (like from a television, smart-phone, computer or tablet, etc.) at least one hour before bed. Blue light is a known sleep disruptor. If you have to have a light, use red or get blue light blocking glasses.
If you are not getting adequate sleep, seek help from a functional medicine doctor well versed in the many behaviors, environmental factors, lifestyle factors as well as medications and supplements that can help you regain a consistent and fully restorative night’s sleep.
Congratulations Alaska on the return to longer daylight hours, but be sure the bedrooms of your home are pitch black for sleeping!
Dr. Summer Beattie,ND was born and grew up in Southeawst Alaska – it will always be home. A 2004 graduate of Bastyr University, she served two terms on the board of directors for the Washington Association of Naturopathic Physicians, and has worked in a variety of primary and specialty care settings. This has given her a broad wealth of experience that she now uses in a unique clinical practice with a focus on rejuvenative physical and aesthetic medicine. Dr. Beattie,ND offers comprehensive care as it relates to physical rehabilitation from a Naturopathic Orthopedic perspective. You can find her and on-line patient programs at www.onehealingmedical.com