A flood of recent studies is giving us new insights into how important getting enough good sleep is for staying healthy, feeling great, and thinking straight. So take a short siesta and check out the slumber stats below.
Sleep deprivation makes you eat more.
Skip sleep, and the next day you’ll eat too many calories from fat and too few from carbs, according to a UPenn School of Medicine study. When subjects were kept from sleeping, a brain region called the salience network, which regulates emotions and bodily sensations like a racing heart, lit up and raised their fat cravings. By the way, if you do pig out, just don’t do it late at night: Eating when the body’s usually asleep can hamper learning, damage memory, hurt the immune system, and even lead to type-2 diabetes, UCLA researchers say.
Napping can reverse the effects of a night of poor sleep.
A couple of half-hour naps can relieve stress and boost the immune system back to “Yup, I got enough sleep” levels, the Journal of Clinical Endocrinology & Metabolism reports. The study, on healthy men 25 to 32, found a lack of sleep increased stress hormones (causing anxiety) and decreased antiviral proteins (stimulating immune response)—but those levels returned to normal after two 30-minute naps the next day.
The sweet spot: seven to nine hours of shut-eye.
Healthy adults ages 26 to 64 should get at least six—but not more than 10—hours of sleep, a National Sleep Foundation study review has decreed. Get less and you’re at higher risk of depression; get more, and you’re 21% more likely to become obese.
Game-day performance could ride on sleep rhythms.
The time of day when your circadian rhythms— internal cycles that control the body’s behavioral/physiological systems—are at their peaks can affect your athletic performance up to 26%, says a study in Current Biology. The peaks come at different times of day for different people, so plan your workouts for when you feel most awake.
Too little sleep can raise blood pressure.
The Mayo Clinic reports that missing a lot of sleep can seriously mess with your blood pressure. The study found that four hours of sleep per night (versus nine) didn’t just negate the BP drop we normally experience when we sleep, it also raised pressure above normal levels during the night.