• Diabetes
• Sleep

Can Skimping on Sleep Add Up to Obesity?

With obesity at an all-time high in America, there’s a lot of talk about possible causes. Many scientists are questioning whether too little sleep could be contributing to the problem.

Ideas that sleep deprivation might lead to weight gain often stem from speculation more than solid fact: Lack of sleep could increase your hunger hormones, cause you to be less active because you are tired or provide you with more time to eat.

Women who slept five hours or less were 15 percent more likely to become obese than women who slept seven hours a night.

A lot of research is under way to explore whether too little sleep could be making us overweight.

These studies, while not definitive, lean toward a link between sleep deprivation and those added pounds:

• University of Chicago scientists reported in 1999 that inadequate sleep over a course of days can disrupt both metabolism and hormones. A study of 11 healthy young adults who got only four hours' sleep for six nights showed a drop in their ability to process sugar in the blood. Some reached the level of a person with diabetes. Another study comparing normal sleepers to those who averaged less than 6½ hours showed that those who got less sleep needed to make 30 percent more insulin to keep their blood sugar levels normal.
• The Nurses’ Health Study followed 68,000 middle-age American women for up to 16 years.  Those women who slept five hours or less were 15 percent more likely to become obese than women who slept seven hours a night. In a related study, younger women who had irregular sleep patterns while working a mix of day and night shifts had a greater risk of developing diabetes and obesity. If you are working shifts, try these tips to improve your sleep.
• Several studies observing children have suggested a link between sleep and weight, but they don’t show conclusive evidence that getting enough sleep lowers a child’s risk of obesity.
• The Harvard T.H. Chan School of Public Health reported that two large trials currently under way in the U.S. and New Zealand are testing whether good sleep and feeding habits in newborns help prevent obesity in the toddler years. These studies may produce more conclusive evidence on the connection between sleep time and obesity.  
• Making an indirect link between lack of sleep and obesity, recent research at Cedars-Sinai Medical Center in Los Angeles demonstrated that one night of sleep deprivation can have about the same effect on insulin production as six months on a high-fat diet. In this animal study, researchers looked at how the body became less sensitive to insulin with either lack of sleep or a high-fat diet. Researchers affirmed the importance of sleep to keep a healthy level of blood sugar and help prevent obesity and diabetes.

Sleep Apnea and Obesity

An estimated 18 million Americans have sleep apnea — pauses in breathing that disrupt restful sleep — and about half are overweight. It’s true that losing weight often improves sleep apnea, but it’s less clear that the sleep disorder causes the weight gain. 

The case is still being made for the link between inadequate sleep and obesity. More rigorous clinical trials may answer the question. While the jury is out, there is plenty of evidence that getting enough sleep benefits your overall health. A consistent bedtime, limiting caffeine by late afternoon and keeping electronics out of the bedroom are building blocks for good sleep. 

When you get seven to eight hours of sleep each night (and more if you’re a child or teen), it can pay off with improved performance at work or school, elevated mood and better energy levels.

Source: National Sleep Foundation, The Obesity Society, Harvard T.H. Chan School of Public Health