I saw this news item from the AP about a study on the association of the lack of sleep and obesity in kids age 9-12. The AP piece quotes another sleep researcher about the hypothesized mechanism:
Lack of sleep plays havoc with two hormones that are the "yin and yang of appetite regulation," said endocrinologist Eve Van Cauter of the University of Chicago, who was not involved in the new study.
In experiments by Van Cauter and others, sleep-deprived adults produced more ghrelin, a hormone that promotes hunger, and less leptin, a hormone that signals fullness.
Another explanation: Tired kids are less likely to exercise and more likely to sit on the couch and eat cookies, Lumeng said.
Below is the full citation from Pediatrics and the abstract from PubMed.
Pediatrics. 2007 Nov;120(5):1020-1029.
Shorter Sleep Duration Is Associated With Increased Risk for Being Overweight at Ages 9 to 12 Years.
Lumeng JC, Somashekar D, Appugliese D, Kaciroti N, Corwyn RF, Bradley RH.
300 N Ingalls Building, 10th Floor, University of Michigan, Ann Arbor, MI 48109-0406. email@example.com.
OBJECTIVE. The potential association between short sleep duration or sleep problems and childhood overweight has not been well described. The objective of this study was to test the independent associations of sleep duration and problems with overweight risk in children. METHODS. Data from the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development were analyzed. In 3rd and 6th grades, sleep duration and problems were obtained by maternal report, and height and weight were measured, with overweight defined as a BMI of >/=95th percentile for age and gender. Logistic regression evaluated the association of sleep duration and problems with overweight at 6th grade cross-sectionally adjusting for gender, race, and maternal education. Additional covariates tested individually included the level of chaos at home, the quality of the home environment, the lax-parenting subscale score of the Raising Children Checklist, and the Child Behavior Checklist internalizing and externalizing subscale scores. Logistic regression also evaluated the relationship of sleep duration at 3rd grade and overweight at 6th grade, adjusting for gender, race, maternal education, and the child's BMI z score in 3rd grade. RESULTS. Of 785 children, 50% were male, 81% were white, and 18% were overweight in 6th grade. Shorter sleep duration in 6th grade was independently associated with a greater likelihood of overweight in 6th grade. Shorter sleep duration in 3rd grade was also independently associated with overweight in 6th grade, independent of the child's weight status in 3rd grade. Sleep problems were not associated with overweight. CONCLUSION. One preventive approach to overweight may be to ensure adequate sleep in childhood.
PMID: 17974739 [PubMed – as supplied by publisher]