Why the School Day Should Start Later: Sleep and Obesity

I remember the feeling of having to peel myself out of bed as a child–the crack of dawn, cold…even dark outside while I prepped for school. We know that adolescents naturally start to stay awake later at night (their circadian rhythms tell them to do it). Add in texting and other late night distractions and you’ve got a true night-owl on your hands.

We hear a lot about how drowsiness affects a kid’s academics and mood. But what doesn’t get enough air time is that sleep is strongly tied to weight gain too.

A study released this week in the journal Sleep reports that teens who don’t sleep enough are more likely to eat fatty foods than their well-rested peers. Sleep-deprived adolescents consumed 2.2 percent more calories from fat, and for each hour subtracted from nighttime sleep, a teen is 21 percent more likely to consume a high number of calories from snacks.

Consider how the bump in calories adds up daily–the researchers think the tweaks to a person’s diet cause weight gain and contribute to the rising incidence of obesity in this country.

It’s not a new concept, as readers of Nurture Shock will remember, that the “lost hour” of sleep is linked to weight gain. So why do fewer nighttime zzz’s add up to snacking and fatty foods?  And how much sleep do our kids need to avoid this problem?

The teens in the study who sleep fewer than eight hours were the ones who packed in the calories. The American Academy of Sleep Medicine says teens need at least nine hours of sleep per night. (Children ages 5 to 12 need at least 10, three to five-year-olds need at least 11, and one and two-year-olds need at least 12.5, including naps).

Disrupting sleep sends the body’s biological clock out of whack, which trips off a whole cascade of altered hormones that influence mood and appetite. The short story–a donut is more likely to end up in your hands. I (and some of my fellow bloggers are with me here) can attest to this phenomenon.

And I wouldn’t be surprised if even my two-year-old falls victim to this pattern–I’ll be watching his sleep and his tendency to ask for just one more serving of “ice tweam.”

Image: Everystockphoto/Brianfit

More from Heather Turgeon:

Antipsychotic Medications for Toddlers?

The Bed Bug Mystery: Why They’re Clean and Why They’re Back.

Worried About Dad: Study Says Men With Trouble Sleeping Four Times as Likely to Die.

C-Section Twice as Likely When Doctors Induce Labor.

Why I Abandoned the “Readiness” Approach to Potty Training.

Are Babies Sleeping Less These Days?  5 Nap Tips and More.

Judge’s Ruling Blocks Stem Cell Work.  Is it Even More Restricted Than Under Bush?

Dad’s and Babies Re-Wire One Another’s Brains.  So What if He’s Not Around?

Circumcision Rates in the U.S. Falling Fast.

Article Posted 6 years Ago
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