Tag Archives: sleep debt

Late Bedtimes Add Weight in Children

Our children are staying up later and sleeping less. New research confirms that sleep debt contributes to obesity in young children.

Researchers at the University of Virginia analyzed a large sample of 4 and 5-year olds from the Early Childhood Longitudinal Study–Birth Cohort. The timing and duration of sleep were noted by parents of these children by a questionnaire.


  • Obesity was more likely in for children sleeping less than nine and one-half hours a night.
  • Obesity was more likely for 5 year-olds going to bed at 9 PM or waking before 6:30 AM.
  • Sleeping more would be an easy remedy. Parents could catch some more shut-eye too.

The study appears in Pediatric Obesity.


No Sleep Leads to Big Portions

Scientists publishing in December’s issue of Appetite journal compared portion sizes in young men after a night of sleep and after an entire night without sleep. The researchers from Sweden and the UK found that after total sleep deprivation, the men had raised ghrelin, the hormone that increases hunger. Indeed, the subjects chose larger portions than when they had gotten a regular night of sleep. The supersizing continued as they snacked throughout the day.

But even short sleeps will play havoc with hormones. In earlier experiments at another university setting, students limited to 4 hours for two nights, ghrelin levels increased and leptin levels decreased.

The increased appetite and probable weight gain which comes with short and disturbed sleep—or zero sleep as in the European evidence—may be manageable if it is random, such as studying for a big exam or New Year’s Eve. But for night shift workers, it presents serious challenges.

One solution is to defend against the greedy ghrelin and lazy leptin. How? Keep lots of low-calorie foods and snacks at the ready. Then when you start foraging at 5 AM, your kitchen will offer fruit salad, creamy yogurt, popcorn, favorite soups…anything but the ice cream and cookie trap. Plan ahead.