In simple terms, we need sleep to recover, grow and learn. It is during sleep that our body repairs and our brain integrates new knowledge and forms new associations. A good night sleep depends on coordinating your sleep habits with your circadian rhythm. Circadian rhythm is a built-in biological clock that lasts about 24 hours and can be adjusted or reset by daylight. Many of your body’s biological processes are dependent on circadian rhythm.
Now let us look at how your body responds during a normal sleep cycle and what can happen to alter your circadian rhythm.
Beginning at about 6 am a combination of low body temperature and exposure to morning sunlight contributes to the release of cortisol. Cortisol acts to wake-up your brain and body. Other hormones also have wake-up functions such as increased heart contraction, widening of blood vessels and increased blood sugar. Sunlight also shuts down melatonin production and resets your circadian rhythm. This is why exposure to morning sunlight is important for maintaining a normal sleep cycle.
At sunset your blood pressure and body temperature reach their peak. Leptin is released to shut down your appetite and control late night food cravings. Your body switches to burning fat to create heat while you sleep. It is very important for good sleep to limit bedtime snacking of carbohydrates and proteins because this will spike insulin levels and supress fat burning. If you must snack at night, eat a small amount of a healthy fat like coconut oil.
At 10 pm melatonin secretion starts provided you are in darkness. High levels of artificial light especially blue light from computer screens and TV’s can delay or suppress your melatonin levels. Melatonin acts to shut down waking brain activity and make it easier for you to fall asleep. A good time to go to bed is between 10:30pm and 11:00pm to take advantage of the effects of the increased melatonin.
By midnight, melatonin secretion has peaked. Prolactin is released which increases cell growth and repair. Prolactin also prompts the release of growth hormone and DHEA. Lack of sleep can lower levels of these two hormones and result in increased inflammation and reduced muscle repair. In women, this can lead to early menopause and other hormonal imbalances.
Between 2 am – 6 am, your body temperature falls to its lowest point. This facilitates the repair and growth of your nervous system, strengthening of your immune system and a decrease in inflammation.
It is also important to note that humans are naturally polyphasic sleepers. Our circadian rhythm wants us to sleep three times a day rather than one continuous sleep. In the absence of artificial light sources, humans naturally want to go to sleep about 2 hours after sunset. Then we wake-up after a few hours of sleep. The second sleep occurs a few hours before dawn. The third sleep is in the form of an early afternoon nap.
Although a polyphasic sleep routine may not be practical in our modern world, it is generally a good idea to listen to your body and sleep when you are tired. A 20-minute afternoon nap can be very beneficial.
To get the best possible sleep follow these simple guidelines. Get plenty of exposure to daylight especially in the morning. Do not eat sugary foods or protein as a nighttime snack and limit artificial light exposure before bedtime.
About the Author: Greg Elder is the owner of Resteze an online store specializing in organic and natural bedding.