According to recent research, sleep is as important for health as diet and exercise. Lack of sleep raises blood sugars and insulin resistance. With enough sleep, our bodies can heal and repair. Without sleep, they get sicker.
Poets have celebrated the importance of sleep for centuries. Shakespeare called it the “Balm of hurt minds, great nature’s second course, Chief nourisher in life’s feast.” Now science is catching up. We’re finding that life is tough, and to function, our bodies and minds need rest.
Sleep gives our brains time to learn. According to the National Heart, Lung, and Blood Institute, people remember a day or a lesson better if they have a good night’s sleep.
Sleep gives our bodies time to repair. Our immune systems can work better when our muscles, brains, and digestive system aren’t competing with them for resources. So if your blood vessels or your heart or kidneys need healing (which is the case for many of us), you need to sleep.
Sleep deprivation is associated with raised levels of the stress hormone cortisol. Cortisol triggers insulin resistance. Sleep deprivation also lowers levels of the “I’m OK” hormone leptin, which controls appetite. It raises levels of the “eat more” hormone ghrelin. So less sleep leads to more eating and probable weight gain.
Sleep gives us a break from endless mental stress. From a spiritual point of view, sleep may be like meditation — it’s a time when our minds can be free of the world’s stresses and our own craziness. Then we can see life and our place in it better. Studies show that people who get enough sleep can concentrate and focus longer and more effectively. They tend to be more creative and better problem solvers.
With Type 2 diabetes, lack of sleep is a strong predictor for getting the disease. With any type of diabetes, poor sleep seems to raise glucose levels.
Sleep is hard to get
Our society conspires against sleep. Blame Thomas Edison. Before the electric light, normal sleep time was about 10 hours each night. Edison believed people didn’t really need sleep. Now “healthy sleep” is usually thought of as 7–8 hours, but 30% of Americans get 6 or fewer hours, sometimes a lot fewer.
A recent article in The Atlantic found that poor Americans who work more than one job are lucky to get five hours of sleep a night. The impacts on their health and lives are huge. One study on 147 adults found that sleep deprived subjects had “actively shrinking brains.” Rodent studies have found that the brain cells of sleep-deprived mice “began dying off after just days, and the loss was permanent.”
In fact, most of the increased diabetes in low-income people and discriminated-against people can probably be explained by lack of sleep. A study in 2006 of 161 African-Americans found that 71% reported poor quality sleep. Their average HbA1c level was 8.3%. The less sleep they got, the higher their A1C tended to be.
Being poor is stressful, and stress is a major reason we don’t sleep. Another reason is lack of exercise. If our bodies don’t move during the day, they won’t want to stay still at night.
I’m having this problem big-time now as my abilities to move shrink because of multiple sclerosis. I find if I don’t force myself to walk in the apartment, I can’t sleep more than four hours.
What kind of exercise should we do and when should we do it? Quinn Phillips wrote here that morning exercise greatly improves sleep, but evening exercise doesn’t necessarily help, and may even interfere with it. In the evening, we should do gentle stuff such as mild stretching that doesn’t raise our body temperature or heart rate.
But reader Kristen commented that she started riding her stationary bike in the evening and found no difference in sleep, but her fasting blood sugar is much lower on mornings after she exercises. So she now does half her exercise program in the evening. Everybody is probably different when it comes to timing of exercise, but we all need to move some.
Relaxation is obviously important for getting to sleep. I have written about sleep strategies before and will write more next week. But simple things we know — avoid caffeine and nicotine and chocolate in the evening. Try to keep a regular schedule and don’t nap too much.
Don’t watch loud or disturbing TV or movies in the evening or in bed. You want bed associated with sleep and good times only. Make sure your room is a comfortable temperature and is protected from light and noises as much as possible.
Sleep is important. Sleep is our time of peace. Most of us need more than we get. Next week we’ll look more at things that block sleep and how to treat them.
How are you sleeping? What do you notice interferes with your sleep, and what helps you sleep better?