You might have read that lack of sleep could be a factor if you're gaining weight—but is this really true?
Researchers have indeed found that sleep deprivation can throw hunger hormones out of kilter, increasing one called ghrelin, which stimulates hunger, and decreasing levels of a "weight friendly" hormone called leptin, which suppresses appetite. Ghrelin is produced in the stomach for hours after a meal, continuing to promote hunger. Conversely, leptin is produced in the fat cells and promotes a feeling of fullness or satiety.
Scientists at the University of Wisconsin and at Stanford University tracked over 1.000 people, ages 30 to 60, administering blood and sleep tests to them every 4 years. Their findings: Subjects who typically slept 5 hours a night had 14.9 percent more ghrelin production in their stomachs than did those who slept 8 hours. People in the study who slept less than 7.7 hours a night also had slightly higher body mass indexes (BMIs).
According to the National Sleep Foundation, 63 percent of Americans don't get the recommended 8 hours of sleep a night. And since approximately 65 percent of Americans have issues with overweight and obesity, perhaps sleep deprivation could be associated with some of that weight gain. And here's another possible link: overweight people have a significantly higher incidence of obstructive sleep apnea (OSA), a disorder that is also associated with higher weight.
One study from Columbia University that looked at the sleep patterns and obesity rates of over 6,000 people found that people who slept only 2 to 4 hours a night were 73 percent more likely to have issues with obesity than those who slept 7 to 9 hours; that those who got about 5 hours of sleep were 50 percent more likely to be obese than were those who got 7 to 9 hours; and that people who slept roughly 6 hours a night were 23 percent more likely to have problems with obesity.
Factors that may disrupt sleep
Research has shown that obstructive sleep apnea (OSA) not only can disrupt sleep significantly (including REM, or active dream sleep), but can also skew hunger hormones, increasing levels of hunger-inducing ghrelin.
Alcohol has also been reported to disrupt REM sleep, and it increases levels of hunger hormones upon waking, a combination that is not weight friendly (never mind all the calories in alcoholic drinks).
Night-shift workers, who are known to have sleep-cycle disturbances and alterations, have consistently been found to be heavier than their daytime colleagues.
If you're eating a healthy diet and getting regular physical activity but are still having trouble with your weight, take notice of whether you're getting enough sleep—you might be missing out on the important link between lost sleep and increased hunger pangs. And if you're dealing with increased weight and your significant other says you snore, or you're waking up exhausted every morning, talk to your doctor about the possibility of having a sleep study to rule out OSA.
No matter what your weight, see if you might need more sleep. A good rule is to "catch up" on your sleep in the early part of a vacation and then, after the first few days, notice how much sleep your body actually seems to need. Try to get that optimal amount every night during the rest of your days off and see how you feel.
Good sleep hygiene also involves not stimulating your brain right before bedtime (news and crime shows can shift your brain into overdrive). Also, try to relax within an hour of going to bed, perhaps with a warm bath or a calming book.
Sleep well, my dear readers!