Are Our Kids Getting Enough Sleep?

Think your kids are getting enough sleep? I know I did. Think again.

NY Magazine writes about some groundbreaking studies being done that tie our children's performance in just about every arena to the amount of sleep they are getting at night. And the results are pretty eye-opening.

One study, done by a doctor at Tel Aviv University, showed just how detrimental missing that hour of sleep actually can actually be to our kids' cognitive abilities:

The effect was indeed measurable—and sizable. The performance gap caused by an hour’s difference in sleep was bigger than the normal gap between a fourth-grader and a sixth-grader. Which is another way of saying that a slightly sleepy sixth-grader will perform in class like a mere fourth-grader. “A loss of one hour of sleep is equivalent to [the loss of] two years of cognitive maturation and development,” Sadeh explains.

Sadeh’s findings are consistent with other researchers’ work, all of which points to the large academic consequences of small sleep differences. Dr. Monique LeBourgeois of Brown University studies how sleep affects pre-kindergartners. Virtually all young children are allowed to stay up late on Fridays and Saturdays. Yet she’s discovered that the sleep-shift factor alone is correlated with performance on a standardized school-readiness test. Every hour of weekend shift costs students seven points on the test. Dr. Paul Suratt of the University of Virginia studied the impact of sleep problems on vocabulary-test scores of elementary-school students. He also found a seven-point reduction in scores. Seven points, Suratt notes, is significant: “Sleep disorders can impair children’s I.Q.’s as much as lead exposure.”

Every study done shows a similar connection between sleep and school grades—from a study of second- and third-graders in Chappaqua to a study of eighth-graders in Chicago. The correlations really spike in high school, because that’s when there’s a steep drop-off in kids’ sleep. Dr. Kyla Wahlstrom of the University of Minnesota surveyed more than 7,000 high schoolers in Minnesota about their sleep habits and grades. Teens who received A’s averaged about fifteen more minutes sleep than the B students, who in turn averaged eleven more minutes than the C’s, and the C’s had ten more minutes than the D’s. Wahlstrom’s data was an almost perfect replication of results from an earlier study of more than 3,000 Rhode Island high schoolers by Brown’s Mary Carskadon. Certainly, these are averages, but the consistency of the two studies stands out. Every fifteen minutes counts.

Equally persuasive is this report from some school districts who chose to give their kids an extra hour of sleep based on the emerging data that points to importance of a good night's sleep:

Convinced by the mountain of studies, a handful of school districts around the nation are starting school later in the morning. The best known of these is in Edina, Minnesota, an affluent suburb of Minneapolis, where the high school start time was changed from 7:25 a.m. to 8:30. The results were startling. In the year preceding the time change, math and verbal SAT scores for the top 10 percent of Edina’s students averaged 1288. A year later, the top 10 percent averaged 1500, an increase that couldn’t be attributed to any other variable. “Truly flabbergasting,” said Brian O’Reilly, the College Board’s executive director for SAT Program Relations, on hearing the results.

Another trailblazing school district is Lexington, Kentucky’s, which also moved its start time an hour later. After the time change, teenage car accidents in Lexington were down 16 percent. The rest of the state showed a 9 percent rise.

Studies also show that another side effect of too little sleep would seem to be a slowed metabolism:

Five years ago, already aware of an association between sleep apnea and diabetes, Dr. Eve Van Cauter at the University of Chicago discovered a “neuroendocrine cascade” that links sleep to obesity.

Sleep loss increases the hormone ghrelin, which signals hunger, and decreases its metabolic opposite, leptin, which suppresses appetite. Sleep loss also elevates the stress hormone cortisol. Cortisol is lipogenic, meaning it stimulates your body to make fat. Human growth hormone is also disrupted. Normally secreted as a big pulse at the beginning of sleep, growth hormone is essential for the breakdown of fat.

It’s drilled into us that we need to be more active to lose weight. So it spins the mind to hear that a key to staying thin is to spend more time doing the most sedentary inactivity humanly possible. Yet this is exactly what some scientists seem to be finding. In light of Van Cauter’s discoveries, sleep scientists have performed a flurry of analyses on children. All the studies point in the same direction: On average, children who sleep less are fatter than children who sleep more. This isn’t just in the U.S.; scholars around the world are considering it, as they watch sleep data fall and obesity rates rise in their own countries.

Three foreign studies showed strikingly similar results. One analyzed Japanese elementary students, one Canadian kindergarten boys, and one young boys in Australia. They all showed that kids who get less than eight hours of sleep have about a 300 percent higher rate of obesity than those who get a full ten hours of sleep. Within that two-hour window, it was a “dose-response” relationship, according to the Japanese scholars.

In Houston public schools, according to a University of Texas at Houston study, adolescents’ odds of obesity went up 80 percent for each hour of lost sleep.

Sooo. That extra cup of water, the extra few minutes watching the game, the late hour at which they actually settle down and get their homework done, the early rising to catch minyan at school (for those boys who are Bar Mitzvah) - all could potentially be setting our kids' cognitive functioning and physical health back in a very real, very measurable way. The reason that is such a bitter pill for me - and likely many fellow parents of of school-age or older children - to swallow, is the simple fact that it just does not seem possible for my kids to manage all that needs to be done on a school night, plus a bit of downtime before the deadline rears its ugly head for what this study seems to consider a reasonable bedtime. Consider the long school hours Yeshiva kids put in (pretty much dawn to dusk this time of year), add numerous subjects' worth of homework (at least an hour's worth nightly for some kids), throw some extra-curricular activities into the mix (I am not taking away their only shot at getting some decent exercise when winter comes around), and as it is you have a day with far too few hours in it. Add an earlier bedtime to the mix? I would venture to guess that for many households, it almost feels like it just can't be done.

Obviously, with studies as compelling as these, I'm not giving up just yet - but how in the world does one get teenagers to settle in at a reasonable hour? Or force a wired school-age child to actually fall asleep at bedtime - and not just lay in bed? Cut back on studying for tests so that kids can go to sleep earlier and potentially reap those cognitive gains?? Uh, but what if there simply isn't enough time to actually review all the material? Which is more important to better test performance - more hitting the pillow, or more hitting the books? And is anyone really willing to bet that it's indisputably healthier for our kids' - many of whose physiques are, let's face it, sorely in need of some physical activity - to cut back on any extracurricular sports that might push back their bedtime for fear of them...getting fat??

As I said, these studies all seem very persuasive, and I will admit that I already announced to the Ortho offspring that from here on in, everyone must be in bed at his or her appointed bedtime (can't blame a mom for trying). But who's to say that said bedtimes will even be early enough? And how many hours exactly make up the elusive gold standard that constitutes "enough sleep"? I don't see any guidelines in the article as to how much sleep is enough - only some hints as to how little is too little. Anyone?