If you want to maintain a healthy weight, make sure you get enough sleep. New research has found that sleep deprivation can lead to obesity and diabetes. The studies suggest that adequate sleep could be just as important as diet and exercise in the preventive health equation.
Sleep and metabolism
Research has shown that disruptions in circadian rhythm such as jet lag and shift work can increase the risk of obesity and diabetes. But scientists haven’t been exactly sure how sleep deprivation affects metabolism. A new review of sleep deprivation studies by Dr Kristen Knutson, from the University of Chicago outlines how sleep disturbances impact appetite regulation, impair glucose metabolism and increase blood pressure.
Appetite deregulation
Knutson’s report summarizes how sleep deprivation disrupts secretion of the brain signal hormones ghrelin and leptin. Ghrelin, the so-called hunger hormone, stimulates appetite. Leptin signals the body that it is satiated. Essentially, lack of sleep de-regulates appetite and leads to increased food intake. The evidence Knutson accumulated evidence associated increased body mass index or obesity with getting fewer than six hours of sleep.
Disrupting circadian rhythm
To learn more about how sleep deprivation and disruptions in the body clock affect the metabolism, Researchers at Harvard Medical School recruited 21 volunteers who would have their sleep-wake cycles disrupted in a laboratory setting for five weeks. Previous studies on disruptions in circadian rhythm only lasted up to two weeks.
Three weeks before the experiment began, researchers asked the volunteers to sleep up to 10 hours a day. Then they were moved into isolated laboratory suites. During the study, normal time cues were removed and the volunteers were allowed about five hours of sleep every 28 hours, randomly spaced over various times of day and night.
Sleep deprivation and weight gain
After five weeks, researchers measured their resting metabolic rates and insulin and glucose levels. Their average metabolic rate was 8 percent lower than before the sleep disruption period began. The researchers noted that such a metabolic slowdown could put on 10 to 12 pounds in a year, even if diet and exercise habits remained unchanged.
Increased diabetes risk
The experiment also revealed metabolic changes that increased the risk of developing diabetes among the volunteers. After five weeks of sleep deprivation, their insulin levels dropped by about 33 percent. With less insulin their blood sugar levels dramatically increased. Three of the participants reached a clinical prediabetic state. Fortunately for the volunteers, their blood sugar levels returned to normal as they were monitored during a nine-day recovery period.
The big three
According to Knutson, 18 percent of adults in the U.S. get less than 6 hours of sleep—about 53 million people at risk for obesity and diabetes. Without enough sleep, it’s hard to find the energy to exercise. You have a tendency to eat more and make poorer food choices. These recent studies show that sleep is just as important as diet and exercise for your health.
Source: Science Daily, TIME, Los Angeles Times