We’re all guilty of using the term “I’ll sleep when I’m dead” at some point in our lives. It’s strange to think that from an evolutionary perspective, we were designed to be sleeping for approximately one third of our lives! Of course, if we didn’t have to sleep, we would have close to 3,000 more hours in a year to explore, learn, work, and much more. But if sleep was really unimportant, our need for sleep would have selectively decreased over time. So let’s dive into the reasons why we need sleep, and what happens when we don’t get enough. 

Sleep is imperative for overall restoration of our brain and body. Throughout the day our brain is using energy in making connections, thinking and learning. These complex reactions create toxic by-products that must be eliminated or they are subject to cause memory issues, decreased neural communication and inflammation.  Sleep is what allows our brain to detoxify and remove these harmful by-products. 

During sleep the body prioritizes several functions. Research shows that different areas of the brain are stimulated, some that are responsible for memory formation and processing in particular, which is why studying before bed can be extra effective. Activity of immune cells are also higher at night, making sleep important for longevity. Our metabolism is slowed down at bedtime to help us conserve energy and produce more growth hormone, building us a better “house”. Finally, neural connections are made stronger at night, supporting the health of our cognitive function. 

Good sleep is a game of both quantity and quality. While there are many levels of sleep, the most restorative level is called “deep sleep”. During this period our blood pressure drops along with our core body temperature. This cooling state shrinks the brain slightly and allows us to clear toxic metabolites and repair our brain with the help of growth hormone and cytokines released by white blood cells. If we fail to get into this deeply restorative state, we miss out on a vast opportunity to rejuvenate our mind and body. 

Sleep helps to keep our body in homeostasis. Sleep deprivation can impact our diet, lifestyle, performance, cognitive function and ability to recover optimally. People who get less than 7 hours of sleep tend to have a higher caloric intake, diminished food variety and increased snacking. Optimal sleep not only keeps hunger in check, but also may result in weight loss due to a decrease in overall inflammation. 

If we are staying up and night and sleeping at random hours of the day we can throw off our circadian rhythm which requires appropriate amounts of sleep-related hormones, neurotransmitters and chemicals for ideal function. Caffeine can also impact our internal clock, binding to receptors in the brain that would otherwise make us start to feel sleepy, and shutting them off. This is why it’s important to avoid caffeine consumption in the afternoon, especially if we are slow metabolizers of caffeine. Altering our natural cycles can become a vicious cycle as we notice an inability to fall asleep or stay asleep due to the dysregulation of our sleep regulating systems. 

If we truly want to ward off the nursing home and become fit for life, we should realize the value in prioritizing sleep. It also may keep us out of the emergency room as more vehicle accidents are caused by sleep deprived drivers than any other type of impaired drivers. Sleep is a necessary component of overall wellness, and a key to being able to take on anything life throws at us. Let’s give ourselves the advantage of looking, feeling and performing better daily, by simply hitting the pillow sooner, and allowing our bodies to do the rest. (pun intended)


Ballantyne, S. (2017). Paleo Principles. Las Vegas, NV: Victory Belt Publishing.

Borbely, A. A., Daan, S., Wirz-Justice, A., & Deboer, T. (2016). The two-process model of sleep regulation: a reappraisal. Journal of Sleep Research, 131-143. 

Colten, H., & Altevogt, B. e. (2006). Extent and Health Consequences of Chronic Sleep Loss and Sleep Disorders. In H. Colten, & B. e. Altevogt, Sleep Disorders and Sleep Deprivation: An Unmet Public Health Problem. Washington, D.C.: National Academies Press (US).