A common question I get in my practice is “How much sleep should I be getting?” This is a very important question. Last year, the Centers for Disease Control called insufficient sleep a public epidemic. It is estimated that nearly half of all American adults get less than the minimum recommendation of seven hours of sleep per night. With that many people operating on inadequate sleep, fatigue is so common that it’s easy to overlook the serious nature of the issue. However, with insufficient sleep being cited for auto and industrial accidents and increasing a person’s risk of chronic disease, the case for getting enough sleep should be heard.
Sleep and Reaction Time
Sleep studies have consistently shown that “function” (identified by reaction time measured in a variety of tests) is almost 100 percent impacted by sleep. In fact, a NASA-funded study at the University of Pennsylvania showed that people who self-identify as being able to fully function on less sleep actually experienced more substantial delays in reaction time than people who self-identified as needing (and finding a way to get) eight to 10 hours of sleep per night.
While these reduced reaction time results on controlled tests are alarming, the reality is even worse. Lack of sleep by key personnel has been cited in nuclear power plant disasters, the Exxon Valdez oil spill, and the Challenger space shuttle explosion. Maybe your job doesn’t require intense focus, but a lack of sleep can impact the results of everyday activities just as drastically. Law enforcement agencies across the U.S. consider driving a car under the effect of extreme fatigue identical to driving while drunk.
Sleep Habits and Risks for Disease
Lack of sleep’s effect on overall health is also of great concern. Inadequate sleep is known to increase the risk for the following:
- Heart disease
- Heart attacks
- High blood pressure
- Colon cancer
There also seems to be a link between lack of sleep and a higher risk of developing dementia and Alzheimer’s disease. Reduced testosterone levels have been measured in men who reported getting six hours of sleep per night or less.
Not getting enough sleep also negatively affects the immune system. That’s why a person might find oneself coming down with a cold or flu after an extended period of reduced sleep. Studies have shown that T-cell count (which is often used to measure immune system function) is relative to a person’s average amount of sleep. Likewise, there’s a reason your doctor recommends rest when you’re ill: fever response is better while we sleep.
Sleep deprivation can also lead to muscle loss and fat gain. With too little sleep, the body is also more likely to produce the stress-response hormone, cortisol. After sleep deprivation, subjects in several studies had higher levels of cortisol later in the day, a time when it should be tapering off to prepare the body for rest. Heightened cortisol prompts the body to store more fat and be more inclined to use other soft tissue, such as muscle, as energy which means that sleep-deprived dieters lose more muscle and gain more fat than do those who are well rested. One study found that after two weeks of minor calorie restriction (10 percent less than their daily energy expenditure), subjects who were getting 5.5 hours in bed a night lost just 0.6 kilogram of fat but 2.4 kilograms of other tissue, such as muscle. Subjects who got 8.5 hours slumber each night lost 1.4 kilograms of fat and 1.5 kilograms of other tissue. “Some of these metabolic effects occur pretty quickly,” Dr. Mehra – Journal of the Academy of Nutrition and Dietetics.
Oversleeping: Too Much of a Good Thing?
Just as not getting enough sleep is unhealthy, getting too much sleep isn’t a good thing either. There may be times (such as with illness or during periods of excess stress) when your body may feel an increased need for sleep, and this is normal. However, oversleeping on a regular basis should be watched carefully. Researchers acknowledge a strong association between frequent oversleeping and depression and/or other underlying health concerns like heart disease.
Children up to age 12 should aim for about 10 hours of sleep per night, teens should get 9-10 hours per night and adults should get 7-8 hours per night. Naps can occasionally supplement shortened overnight sleep, but sleep cycles depend on a specific chunk of time, so it’s still important to focus on getting a good night’s sleep.
Discuss Your Concerns with a Trusted Physician
Dr. Raman’s Concierge Medical Practice is focused on caring for each patient with comprehensive, individualized treatment options and health programs. Our office is committed to helping find the best solutions for you and your particular needs.
Like many other conditions, sleep disorders affect each person differently and require a very personalized approach to care. For more information on healthy sleep habits, please contact us today or schedule an appointment with Dr. Raman.