The Healing Power of Sleep
3. The Sleep Link to Diabetes
The key underlying problem in type 2 diabetes is insulin resistance, where
the body does not make proper use of this sugar-processing hormone. Guess what?
When you’re sleep deprived, your body almost immediately develops conditions
that resemble the insulin resistance of diabetes.
“In one study of young, healthy adult males, they decreased their sleep time
to about four hours per night for six nights,” says Arand. “At the end of those
six nights, every one of those healthy young men was showing impaired glucose
tolerance, a precursor to developing diabetes.”
Another study found that people in their late 20s and early 30s who slept
less than 6.5 hours per night had the insulin sensitivity of someone more than
60 years old.
4. The Sleep Link to Brain Function and Mental Health
If you’re chronically sleep deprived, you may think you’re still driving
safely and performing well at your job, but you’re probably wrong. Studies have
found that people who aren’t getting enough sleep drive just as unsafely as
someone who’s drunk.
“We also know that people who are sleep deprived have very poor judgment
when evaluating their own performance. They think they’re doing well on memory
or eye-hand coordination tests, but they’re not,” says Arand. “The memory is
also slightly degraded when you’re sleep deprived, and gets worse the more
deprivation you have.”
5. The Sleep Link to Obesity
Can not getting enough sleep really make you fat? Several studies over the
past decade point to a link between sleep deprivation and obesity -- in both
adults and children. In one study, people who slept five hours per night
were 73% more likely to become obese than those getting seven to nine nightly
hours of sleep. In fact, one study found that lack of sleep was a bigger
contributor to childhood obesity than any other factor.
Nobody knows exactly why this might be, but some research has pointed to
hormonal imbalances as the culprit. For example, lack of sleep has been linked
to lower levels of the hormone leptin, which reduces hunger.
The good news in all this is that you can repair the damage from inadequate
sleep fairly quickly. “The system is very quick to respond,” says Arand. “For
example, the young men in the diabetes study returned to a normal state of
glucose tolerance after just a few nights of regular sleep. Many of these
conditions will repair themselves -- unless, of course, you get so chronically
sleep deprived that you’ve caused permanent damage to your health.”