Why Do We Need Sleep?

Getting enough sleep is a necessary component of a healthy lifestyle, but these days, Americans are sacrificing more and more sleep in the name of productivity. Can we actually function well while cutting down on shut-eye? The science says no. In order to function at a high level, most people need at least eight hours of sleep. According to Dr. Colfer, small percentages of people, roughly 3%, can function on 6 hours of sleep, and another 3% need 10 hours. When we deprive ourselves of this essential sleep time, we lose functionality and risk our health in the process.

Getting enough sleep promotes healthy brain function and a stable emotional state. While we’re off in dreamland, our brains process what we’ve learned and experienced during the day and store it in memory. At the same time, our brains make the neurotransmitters that help control our mood. No wonder a sleepless night can leave us feeling grouchy! To top it all off, our sleep time is when our brains make brain-derived neurotrophic factor (BDNF), which acts as Miracle-Gro for the brain. This protein allows allows for cellular remodeling, dendritic pruning, and enhanced NT function at the synapse. It also enhances neuroplasticity/neurogenesis. Sleep promotes this protein, thereby encouraging healthy brain function.

Going without sleep not only decreases sleep’s positive effects, but also increases the possibility of health complications. The consequences of sleep deprivation can be immediate and obvious, like a car crash, or they can be more insidious. Over time, insufficient sleep can cause an increased risk of diabetes and heart disease. Because your immune system is dependent on sleep, you can also weaken your defenses against infections and cancer. It’s proven that women who work the night shift for more than ten years have a large increase in risk for breast cancer. If that’s not bad enough, lack of sleep is also linked to increased risk for hypertension, stroke, heart disease, and diabetes.

The consequences of sleep deprivation aren't always immediate and obvious. Over time, insufficient sleep can cause an increased risk of diabetes and heart disease.

What’s more, the correlation between obesity and lack of sleep is significant. The appetite hormones ghrelin and leptin can become unbalanced with sleep deprivation, resulting in increased appetite and unnecessary eating. When we’re awake longer, we also have more opportunities to eat in our waking hours; at the same time, we also lack the energy to exercise. This combination provides ample opportunity for unhealthy weight gain.

Sufficient sleep counteracts these effects, promoting a healthy balance of hormones such as cortisol, insulin, and growth hormone. And growth hormone is important to more than just kids and teens; for adults, it also allows cells to repair themselves more quickly, enabling faster recovery. We tend to be unaware of how losing even one hour of sleep per night can impact us. People may be adamant that they are high functioning, but tests reveal they are dangerously sleep deprived. When we underestimate the power of fatigue, we place ourselves and others in jeopardy.

Of course, prioritizing sleep is easier said than done in today’s world. Our very culture encourages the notion of sacrificing sleep for productivity. As a result, we all have priorities that we put ahead of sleep, whether it’s staying up to meet a work deadline or to watch one more episode of our latest TV show. But our poor sleep can come from more than over-scheduling. Other causes can include anxiety and depression, hormone imbalances, sleep apnea, and our medications. Even the sweet blue glow of our electronics can disrupt our sleep cycles if we don’t give ourselves a break before bed. And while exercise usually facilitates better, deeper sleep, endurance athletes can struggle with sleeplessness due to cortisol disruption and micronutrient deficiencies.

Yet another cause of sleep disruption is poor sleep hygiene, a concept detailing how your daily routine impacts the quality and duration of your sleep. For more information on sleep hygiene and how to improve yours, keep an eye out for our upcoming post, “7 Tips for Developing Healthy Sleep Habits.”