Many folks believe that sleep is not a big deal. You miss a few hours and you make up for it the next night, or the night after that. Some folks actually brag about how little sleep they get by with. Lucky, yes? It turns out that sleep is not a big deal, it’s a HUGE deal. According to T.S. Wiley, author of Lights Out, sleep deprivation is actually seasonal and for those who get less than 9.5 hours during the 7 “winter months” may actually be setting themselves up for serious health issues Dr. Eve Van Cauter concurs. She found that the metabolic and endocrine changes resulting from sleep deficit look just like aging. “We suspect that chronic sleep loss may not only hasten the onset but could also increase the severity of age-related ailments such as diabetes, hypertension, obesity and memory loss.”
There have been over 1000 studies looking at the effects of sleep so why haven’t we heard about important it is? When queried, Dr. Wehr of the Department of Seasonal Circadian Rhythmicity at the National Institute of Health replied” Well, yes, [the public] has a right to know. They should be told, but it won’t change anything. Nobody will turn off the lights”.
We are a sleep deprived nation. Over 42% are unable to stay awake and another 26% can’t get to sleep. Sleep has become an issue since the advent of electric light. In nature, a person would sleep 12 hours per night. Eighty years ago, the annual value fell 9.3 hours. Now we are sleeping around 7 hours a night.
How cortisol affect sleep?
Since sleep involves complicated systemic interactions throughout the body. We are just going to focus on the effects of the adrenal glands and blood sugar on sleep..
Light /dark cycles are an important part of our physiology. Our bodies adapt to periods of feast/famine by the ability to store fat from carbohydrates (and a few amino acids) via the hormone insulin. During the summer when food is abundant, our ancestors would consume lots of food to produce fat and cholesterol as a means of surviving the harsh “carbohydrate-less” winter. Hormones turned-off appetite suppression. We became insulin resistant which allowed us to store as much fat as possible. This not only nourished us, but the cholesterol would keep our cell membranes from freezing. So basically, long summer days meant plenty of time for food storage and procreation, and the dark cycle (both winter and sleep), allowed regeneration to occur.
So what does this have to do with sleep? Our body is tightly regulated by our endocrine system. The problem with continual short nights is that they simulate summer and the storage of fat.
Lack of sleep interferes with pituitary regulation (HPA axis). The body produces cortisol to respond to any type of stress. One of the things it does is release blood sugar from stored sources to provide the body energy needed to fight the stress. Now, normally cortisol levels decrease from a high level in the morning (since the body had to release sugar all night long to keep us fed) to a low value in early evening. But just like summer, this “long day” causes artificially high levels of cortisol to remain longer throughout the evening (which in turn increases insulin levels in order to store the excess sugar released by the cortisol). And since these levels do not fall until we reach a very deep sleep, cortisol doesn’t rise normally in the morning. This results in a reversal of our normal hormone rhythms. It’s no wonder why many of us are not waking up hungry! In addition to insulin resistance, high cortisol reduces production of growth hormone and robs our amino acids stores which makes it even more difficult for the body to repair itself.
How does light affect sleep?
To enable these physiological changes, our bodies are designed to detect light. Actually, every part of us is able to read changing light intensity and spectrum. Cells called cytochromes pick up blue tones via the skin.This light is sent to our gut bacteria (which require both light and sugar to survive, who knew!). Once fed, the bacteria in our intestines release a waste product called endotoxin LPS. During the course of a day, the immune system eventually responds to the rising levels of LPS by rendering us unconscious! As darkness falls, the body detects the rose tones of sunset and produces a very helpful hormone, melatonin. Melatonin lowers the body temperature to slow our metabolic rate. as well of that as our friendly gut bacteria, which in turn lowers the level of LPS. This allows the immune system to relax which wakes us up (at the same time the green daylight turns off melatonin).
It is important to note, that even small amounts of light can initiate this reaction. At Cornell University, researchers illuminated a patch of skin no bigger than the size of a quarter. All other areas of the body were kept in complete darkness. They were surprised to find that both the subject’s temperature and melatonin levels were noticeably affected!
The proof is in the studies!
Since one of the most profound effects of limited sleep is on blood sugar regulation (and which in itself is the source of many degenerative diseases), let’s look at this interesting study. Researcher enlisted 11 healthy young men to sleep in a specific manner fro 16 consecutive nights. During the first 3 nights, the men slept for 8 hours (11 p.m. to 7 a.m). The next 6 nights, 4 hours (1 to 5 a.m). Finally, they were allowed 7 nights of 12 hour uninterrupted sleep (9 a.m. to 9 p.m.) Diets were identical for all periods and subjects.
What they discovered is that there was so much sugar dysregulation during the periods of limited sleep that they participants actually started to demonstrate patterns of type-2 diabetes. They required 40 percent longer than normal to regulate their blood-sugar levels and insulin sensitivity decreased by about 30 percent. Sleep deprivation also interfered with many other important hormones including TSH, sex hormones, and neurotransmitters.
It is important to note, that these abnormalities quickly returned to normal and actually improved by the end of the 12 hour sleep cycle. This indicates that even eight hours of sleep may not be long enough! Keep in mind, that sine stress can be of any origin: physical, spiritual, and/or emotional. These increased sleep requirements might be due to our bodies response to the daily stress of our “normal” lives.
For those that supplement with melatonin, please note that long term use might cause a reduction in size of the pineal gland over time reducing naturally produced melatonin. Conversely, signs of overproduction of melatonin include needing an alarm or waking up “hungover” since light is no longer suppressing melatonin spontaneously.
How does sleep affect our health?
Chronic sleep deprivation activates the adrenal glands which can lead to health conditions throughout the body. Since we are living a life of perpetual summer, studies have documented that these degenerative diseases have been on the rise. Let’s look at how sleep may contribute to a few of these.
One theory states that heart disease may be on the rise due to high homocysteine levels. Researchers believe that homocysteine might be elevated in some individuals due to the destruction of a crucial pathway enzyme (that can be deactived by a blue light cryptochrome). For others, shear stress due to seasonal high blood pressure caused by elevated cortisol levels along with carbohydrate water weight and serotonin/insulin resistance may seal the deal.
For cancer, it can be summarized as follows: We eat sugar in the summer which increases our insulin levels so that we become insulin resistant. This has caused an increase in estrogen levels and creates neoplastic growth particularly at the reproductive sites that are estrogen stimulated.
What can we do to help improve our sleep?
Obviously it is important to reduce any forms of stress including food intolerance, subclinical infections, dehydration, hormone dysregulation, lifestyle, genetics, etc. You can measure your adrenal activity indirectly and look for underlying dysfunction with Functional Blood Chemistry Analysis. Sleep requires the action of many hormones. Cortisol levels, circadian rhythm, and sex hormones can be measured directly via salivary hormone testing. Diet should be designed to support blood sugar dysregulation.
For those that have an issue sleeping, consider an all protein snack an hour prior to bedtime. Try to get to sleep by 10pm. Supplements such as magnesium, L-theanine, and herbal teas help many folks to relax.
1. Lights Out, T.S. Wiley.
2. Lack of sleep alters hormones, metabolism, Chicago Chronical, 1999.
3. Sleep loss results in an elevation of cortisol levels the next evening.Sleep. 1997 Oct;20(10):865-70.
5. Sleep deprivation effects on the activity of the hypothalamic-pituitary-adrenal and growth axes: potential clinical implications.. Clin Endocrinol (Oxf). 1999 Aug;51(2):205-15.