Are Sleepy Kids at Risk for Obesity?
Children Who Slept the Least Had Greater Risk of Being Overweight
Twice as Many Overweight Kids continued...
One in five boys in the study and about one in four girls were found to be
When compared with children reporting 12 to 13 hours of sleep a night, those
that got 10.5 to 11.5 hours were more than 40% more likely to be overweight or
obese, and those that got eight to 10 hours were almost 3.5 times as likely to
be above normal weight.
The findings are reported in the latest online issue of the
International Journal of Obesity.
Hormones May Hold the Key
If there is a link between sleep and weight regulation, many researchers now
say that hormones may explain it. University of Chicago researchers have shown
that sleep and lack of sleep affect production of two hormones that regulate
Their studies suggest that sleep deprivation was linked to lower levels of
the hormone leptin, which decreases hunger, and higher levels of the
hunger-producing hormone ghrelin.
Robert D. Vorona, MD, who has also studied sleep patterns and obesity in
adults, says the research is fairly consistent but still inconclusive. He
notes, for example, that there is no consensus on how much sleep people
actually need to lower their risk of becoming overweight or to help them lose
"What we can say is that the studies to date show an association between
restricted sleep and obesity," Vorona, who is the Eastern Virginia Medical
School associate professor of medicine, tells WebMD. "What we can't say is
that these studies definitely prove a causal relationship."
In a poll conducted in 2000, the National Sleep Foundation reported that the
average American gets just under seven hours of sleep each night -- about an
hour less than is optimal for most people and about 90 minutes less than most
Americans slept in the 1900s.
Vorona says chronic sleep deprivation alters mood, affects performance, and
is a major risk factor for automobile and work-related accidents.
"There are plenty of reasons to get a good night's sleep," he says.
"And it is very possible that [weight control] is yet another one."