The Importance of Sleep

The three pillars of health are fitness, nutrition and sleep. Sleep could outweigh either of the other two. While you could be active and eat well, not receiving enough sleep has numerous side effects beyond simply being tired.

Sleep helps your body in a variety of ways, ever heard of beauty sleep? We are designed to properly function on the standard 8 hours of sleep a night, while some can operate long term on as little as 6 hours of sleep a night, this is not recommended and could lead to failures in many of the areas listed below. Others need much more, up to 10 hours a day.

Metabolism / Weight Gain: Contrary to what is claimed in the book Insomnia by Stephen King, lack of sleep does not lead to a reduction in body weight. The human body begins to produce higher levels of cortisol when it is awake for extended periods of time. In the study Perceived Stress and Cortisol Levels Predict Speed of Wound Healing in Healthy Male Adults presented in Psychoneuroendocrinology in July of 2004, they showed that people who secrete higher levels of cortisol in response to stress also tend to eat more food, and food that is higher in carbohydrates than people who secrete less cortisol. If you’re more sensitive to stress, it’s especially important for you to get some extra sleep.

Karine Spiegel, PhD, and colleagues published an article in the December 7, 2004 issue of the Annuals of Internal Medicine that suggested that sleep restriction can lead to weight gain. They found that sleep restriction leads to decreased levels of the hormone Leptin and increased levels of Ghrelin, another hormone. The alteration of the levels of these appetite and energy regulating hormones was associated with increased hunger and appetite in the study. This study adds to the evidence linking insufficient sleep to obesity. Leptin is a hormone released by fat cells in the body to indicate if the body is starving or not. The body responds to low levels of leptin by increasing the craving for carbohydrates. The result of less sleep is a lower level of leptin, which then causes extra cravings for food.

Learning: Sleep helps the brain commit new information to memory through a process called memory consolidation. In studies, people who’d slept after learning a task did better on tests later.

Memory: The October 12 2004, New York Times Science section, Dr. Roehrs and his colleagues paid sleepy and fully alert subjects to complete a series of computer tasks. At random times, they were given a choice to take their money and stop. Or they could forge ahead with the potential of either earning more money or losing it all if their work was not completed within an unknown remainder of time.

Dr. Roehrs found that the alert people were very sensitive to the amount of work they needed to do to finish the tasks and understood the risk of losing their money if they didn't. But the sleepy subjects chose to quit the tasks prematurely or they risked losing everything by trying to finish the task for more money even when it was 100 percent likely that they would be unable to finish, said Dr. Roehrs.

Ability to Recover: While you are asleep your body releases human growth hormone to repair damage, both intentional through exercise and unintentional done throughout the day.  If the sleep stage process is interrupted, complete repair of soft tissues is impossible due to the resulting decrease or absence of human growth hormone.

Mood: According to the Harvard Women’s Health Watch, sleep deprivation can lead to irritability, impatience, and apathy. These claims along with flattened emotional responses and the inability to multitask were confirmed in a study conducted by psychologist and sleep expert David F. Dinges, Ph.D., of the Division of Sleep and Chronobiology and Department of Psychiatry at the University of Pennsylvania School of Medicine.

Cardiovascular Health: Many of the same studies have shown that a deprivation in sleep can also lead hypertension and a greater risk of stroke.