Balance in nature is a key element sustaining existence. Balance in how much we sleep (or do not sleep) is important for our physiology.
Now and then a study is published regarding how much sleep is enough for the average person. The numbers vary, ranging from six to eight hours per night. One such study, titled “Behaviorally Assessed Sleep and Susceptibility to the Common Cold,” was conducted by researchers in the Department of Psychiatry at the University of California, San Francisco; the Department of Psychology at Carnegie Mellon University; and the Department of Psychiatry at the University of Pittsburgh Medical Center. This study looked at how sleep, or lack of it affects our immune system.
The aim of this study was to determine whether the amount of sleep predicted incidences of the common cold. The amount of sleep was measured using wrist actigraphy and was measured after viral exposure.
Researchers exposed people who only slept for short periods of time to the common cold virus. Then they watched to see if the study participants would contract the illness. Shorter sleep duration, measured with actigraphy before viral exposure, was associated with an increased susceptibility to the common cold.
So how many hours should you sleep?
Other studies have shown that without factors like bright lights, caffeine, and alcohol consumption, people would sleep for between eight and nine hours per night.
As more studies are conducted, we will learn more about how much sleep is enough. For now we can say: sleeping six hours is not enough. Seven hours may be okay, but eight hours is better.
Before electricity, people would go to bed shortly after dark and wake up at the first light. Since the duration of daylight changes with the season, it means people would most likely sleep longer during winters and less during long summer days.
Do not veer off the path of our human evolution. Make a point to sleep a bit longer during winter.
If you are the type of person who adjusts your sleep duration with the season, share with us how you arrived at such a lifestyle and how you believe it affects your life!