Childhood Obesity Linked to Lack of Sleep
Prominent sleep researcher Dr. Phyllis C. Zee, the director of the Sleep Disorders Center at Northwestern Memorial Hospital, agreed. "There is growing evidence for a link between sleep duration and childhood obesity. What is new … is that perhaps even more important than sleep duration is the effect of day to day variability of sleep wake timing on weight regulation."
Whether sleep is short, interrupted or disordered, researchers believe that lack of shuteye contributes to a supersized waist line by wreaking havoc on metabolism and the endocrine system -- and this is especially true when the body is young and still growing. Gozal said there are numerous studies where sleep deprivation has been shown to disrupt levels of gherlin and leptin, two hormones which regulate hunger and appetite. When the body craves sleep, it interprets it as hunger causing leptin levels to crash and ghrelin levels to spike; this in turn, seems to trigger overeating and may also signal the body to cling to fat stores more tenaciously.
Other studies indicate that poor sleep can throw off the body's biological clocks -- also known as circadian rhythms -- particularly the clock that regulates glucose and insulin, two hormones that when out of balance, are closely associated with weight gain, heart disease and diabetes. Sleep deficit has also been found to elevate levels of cortisol, a hormone that among other things regulates how the body uses energy; elevated cortisol levels have been linked to insulin resistance and a higher BMI.
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