Las Vegas is very much a twenty-four hour town. Many people here have jobs with irregular schedules or work hours that force them to restrict their sleep. Averaging less than five hours of sleep for more than three days at a time is common here. Goodness knows I experienced it regularly in my medical training. There are obvious negative effects that happened when I was sleep-deprived, but at the time I was doing it, we didn’t know much about the insidious effects. Since then, we’ve learned a lot.
Researchers at the University of Chicago were investigating what happens when you are chronically sleep deprived (also known as sleep debt) back in the late 90s. Their experiment was fascinating and still very instructive in trying to figure out the proper role for sleep in maintaining excellent health.
The research took healthy men 18-27 years of age and subjected them to three days of only four hours of sleep (from 1-5 am). They then measured the responses of these men to glucose and measured their insulin resistance. Then they had them sleep it off, averaging ten hours of sleep a night for another five days so they were fully rested and repeated the tests again.
What they found was that this prolonged sleep debt caused them to become prediabetic in a matter of days. The amount of insulin they needed to suppress their body’s glucose production also increased so insulin sensitivity was lower (another marker of metabolic dysfunction).
But it didn’t stop with blood sugar. Thyroid hormone concentrations and the stress hormone, cortisol were all altered by the sleep debt.
Since the development of the electric light, most of us have become a bit more sleep deprived. In 1910 the average person slept nine hours a night, and now our average is seven and a half hours. There is no good evidence to suggest that seven and a half hours will put you into sleep debt. However, there is good evidence for this phenomenon happening when you sleep less than five hours a night.
As we age, our total sleep requirement does drop, so people in the later part of their life may genuinely not need as much sleep as they once did. On the other hand, if someone is chronically fatigued and getting less than seven hours nightly, that is very likely contributing to their symptoms.
Good sleep doesn’t only make your metabolic health improve, it is good for your mood, your ability to think and process information clearly and seems to improve weight. Numerous studies have linked chronic sleep debt to obesity.
But you need to get there with proper sleep hygiene. Most medications that people use to help them sleep, including ones available over the counter, are associated with weight gain.
Sleep hygiene is getting into a routine that instigates the normal sleep response in you. Avoiding caffeine is key. However there are also habits that can help.
Try to fall asleep around the same time nightly. Avoid doing “wakeful” activities in the bedroom. Don’t expose your eyes to bright lights and TV/computer screens in the hour right before bed. And finally don’t try to go to sleep unless you are feeling sleepy.
Herbal teas like chamomile and lavender can be very calming, and one study has even shown kiwi fruit can help induce sleep. In addition to these healthy plant foods, be sure to get adequate, regular sleep and catch up on any sleep debt. Nutrition goes along with sleep and exercise to create greater benefits than any single change alone can give.