Are Your Sleep Patterns Making You Fat?
Lack of sleep may be linked to weight gain, but not because it increases a person's hunger as previous studies have shown. Instead, a group of researchers at the Uppsala University in Sweden have linked sleep deprivation to slower metabolism.
Their study was published in the May 2011 issue of the American Journal of Clinical Nutrition.
The study recruited fourteen male college students and over several days subjected them to three different sleep conditions: normal sleep, no sleep, and curtailed sleep. During this time, changes in their blood sugar, hormone levels, how much they ate, and indicators of their metabolic rate were monitored and observed.
When the participants missed just one night of sleep, they showed a 5- 20% decrease in their bodies' energy expenditure. Energy expenditure is the amount of calories a person needs to burn in order for the bodies' necessary functions (breathing, digestion, etc.) to work properly. Decreased energy expenditure leads to weight gain when a person consumes more calories than their body can burn.
Interestingly, while the men experiencing disrupted sleep showed higher levels of blood sugar, appetite regulating hormones and stress hormones in the morning, their food consumption stayed the same regardless of their sleep pattern. It appears that lack of sleep creates changes in the body’s metabolism, rather than hunger levels.
The researchers were careful to point out that many other factors contribute to obesity and that sleep deprivation is very complicated. When combating obesity, it is just as important to pay attention to lifestyle, exercise, and diet.