Practical Wellness
Before the advent of electricity, winter was a time to rest. People hit the sack early and slept until sunrise. Not anymore. We’re up and running from before dawn ’till the wee hours, and no more so than during the holiday season.
The occasional late night isn’t going to hurt you, but losing even an hour of sleep on a regular basis can take a serious toll on your health. ‘But I exercise and eat well!’ you say. ‘Isn’t that enough?’ According to scientists, no. Nothing substitutes for a solid night of shut-eye. And this is actually good news, because of all the things you can do to take care of your health, getting a good night’s sleep is probably the easiest.
How can something as effortless as sleep be so important? Here is what the latest research has to say.
Immunity and disease
When you’re sleep-deprived, your body produces fewer germ-fighting immune cells, making you more likely to catch the latest cold or flu — three times as likely, in fact, if you snooze less than seven hours per night. And once you’re sick, you’ll have a harder time fighting off the illness. This is partly because fevers, which rise at night to help fight infection, can’t do their job if you’re not sleeping enough.
And don’t assume you’re protected just because you got the flu shot. The Mayo Clinic found that sleep-deprived people have a lower immune response and develop fewer antibodies to vaccines.
People with chronic sleep deficits are also at a higher risk for developing diabetes, a result of metabolic changes that affect insulin resistance in cells.
And if all that isn’t enough to convince you to get more sleep, research shows that people who sleep less than six hours are more likely to die from all causes, including illness, disease, and accidents, than people who get upwards of seven hours a night.
Weight loss
A study published in October in the ‘Annals of Internal Medicine’ found that sleep loss sabotages a person’s ability to lose weight. Overweight dieters were allowed to sleep either eight or five-and-a-half hours a night. Those who slept less had higher blood levels of ghrelin, a hormone that stimulates appetite, promotes fat retention, reduces energy expenditure, and increases glucose production. As a result, the sleep-deprived group was hungrier, had lower resting metabolic rates (a higher metabolic rate allows you to burn more calories doing nothing), and when they lost weight, they lost more muscle and less fat.
Another study, which followed 70,000 women over 16 years, found that women who slept five hours or less a night were 32 percent more likely to gain significant weight and 15 percent more likely to become obese, compared with women who slept seven hours a night.
Memory and learning
These functions require three processes. First, we acquire new information. Secondly, we consolidate, or ‘fix,’ the new material in the brain. Lastly, we recall the information when we need it. Though we acquire and recall information when we’re awake, consolidation happens largely in our sleep.
Deep, slow-wave sleep is important for consolidating fact-based information, such as names, places, and what movie you saw last night. The lighter REM, or rapid eye movement, stage is critical for consolidating procedural memory, or the ‘how-to’ of something, such as learning a dance sequence or playing the violin.
And even though you may be awake when you’re acquiring or recalling information, you won’t do either one well if you’re tired. Studies show that sleep-deprived people have trouble concentrating as well as performing tasks that require memory and logic. Even your judgment and decision making will suffer.
Cardiovascular health
You might think you’re doing enough for your heart by eating well and exercising, but skimping on sleep may raise your blood pressure anyway. When you lose sleep, your body responds with chemical and hormonal changes that can lead to hypertension.
Safety
Fatigue causes more than 100,000 car crashes each year, according to the National Highway Traffic Safety Association. The group most affected? Age 25 and under. Shift workers are vulnerable, too, because their biological rhythms are disrupted.
Mood
Though we don’t need studies to tell us that sleep affects mood, scientists have nevertheless found that when people lose sleep, they feel stressed, sad, angry, and mentally fatigued. Long-lasting insomnia can even lead to depression and other psychological disorders. For this reason, as well as those above, talk to your doctor if you have difficulty sleeping.
