Sleep deprivation is one of the oldest forms of torture. A good night’s sleep is one of life’s best cheap thrills.
There is a gazillion dollar industry built up around sleep products, from mattresses to sleep medication to little aromatherapy pillows. There are a gazillion studies that indicate that the human body really likes to get seven to nine hours of sleep per night on a regular basis. Sleep researchers indicate that 24 hours without sleep results in slower reaction time and judgment impaired to the same degree as having a Blood Alcohol Concentration of more than .10, which is legally drunk in all 50 states.
However, sleep deprivation can be a matter of “nerd pride” at MIT. Some view being severely sleep deprived as an academic badge of honor. Ironic, considering many studies, including one published in the January 2008 issue of Behavioral Sleep Medicine, find that college students who sleep less perform worse academically. Sleep not only helps to consolidate memory and learning, it helps to minimize the damage sleep deprivation causes to one’s cognitive and social intelligence.
So, how can we minimize our own brain damage? How can we get better quality sleep, even if we aren’t getting optimal quantity?
If you find yourself pulling one all nighter, try to clear your schedule the next night so you can get to sleep as early as possible. This will minimize the disruption to your sleep-wake cycle and get you back on track to deep, restorative sleep sooner.
If you have chronic sleep deprivation, try to time your naps so they have the best impact and the least disruption to your sleep-wake cycle. A 20–30 minute power nap can be refreshing without creating too much “sleep inertia” or lethargy upon awakening. If you have a huge sleep deficit, you might choose to take a 90-minute nap, which allows the body to go through deep sleep and come back up into a lighter stage of sleep, making it easier to wake up. Ideal timing is mid-afternoon (I mean no disrespect to those 2:30 p.m. classes).
Lack of deep sleep is strongly implicated in American weight gain. In two recent sleep studies, researchers have identified major weight and diabetes risks associated with inadequate sleep. In the Nurses Health Study (August 2007), subjects who slept five hours per night were 32 percent more likely to gain 33 pounds or greater and 15 percent more likely to become obese than subjects who slept seven hours per night. So seven hours of sleep per night appears to be a tipping point for some people to protect against weight gain.
In another study, healthy young adults deprived of slow-wave sleep for just three nights developed insulin resistance — associated with increased diabetes risk — comparable to a 20–30 pound weight gain (University of Chicago, December 2007). Deep, slow-wave sleep is really important, so try to make your sleep environment as conducive as possible by keeping it dark (or wearing a sleep mask), quiet (or by using a white noise machine or earplugs), and on the cool side.
Exercise in the morning or afternoon helps promote more deep, restorative sleep at night. If you work out in the evenings, make sure your body has cooled off a lot before going to bed. A drop in body temperature is a hallmark of a strong sleep cycle.
Finally, the body’s stress response (“fight or flight”) is the enemy of deep sleep. Increases in cortisol from stress or drinking alcohol interfere with deep sleep states. Learn how to evoke your own “relaxation response” (yes, everyone has one — this is the biological opposite of the fight or flight response) to help you get to sleep faster and stay in a deeper stage of sleep. Try using the relaxation techniques led by yours truly on the MIT Web site: http://web.mit.edu/medical/wellness/stressless/.
Susanna “Zan” Barry is a health educator at the Center for Health Promotion and Wellness at MIT Medical. She can be reached at firstname.lastname@example.org.