Cathy Arnst

There has been a flurry of stories recently that establish what many of us already know to be true based on our own memories: the 'tween years are the worst. The latest proof of the terrible burden of adolescence is a report, from the Journal of Pediatrics, that girls are at greatest risk of becoming overweight between the ages of 9 and 12--and girls who are overweight at those ages are at much higher risk of obesity, heart diesase and diabetes as adults. The stats:

Some 7.4 percent of white girls and 17.4 percent of black girls already were overweight by age 9. Each year through age 12, between 2 percent and 5 percent of the remaining girls became overweight, reported Douglas Thompson of the Maryland Medical Research Institute. After the girls reached 12, new cases leveled off to between 1 percent and 2 percent a year.

The researchers did not give reasons for the trend, but other studies have found that girls become much less active after the age of 10. Dr. Denise Simons-Morton, who heads obesity-prevention efforts at the National Institute of Health's National Heart, Lung and Blood Institute, sums up the problem pretty well in an AP story on the study:

Other research has shown that the preteen years are when youngsters switch from heeding parents' dietary advice to eating like their friends do, Simons-Morton said. Less physical activity plays a role, too. She recalls from her own daughters' tween years long sedentary hours on the phone and worries about getting sweaty.

If nothing else, this study should be a warning for parents of pre-tween children. Just because they are thin now doesn't mean you shouldn't worry about what they're eating. A diet rich in junk food can quickly turn a skinny nine-year-old into a fat 12-year-old, and why saddle them with those additional pounds at a time when they are already having problems with self-esteem and body image.

Part of the problem is that many parents of chubby kids are in denial about their own child's weight problem or eating habits. According to a story in today's New York Times , some states and school districts are trying to force parents to face facts by sending home "obesity report cards" with the child's body-mass index. The results are very mixed. The school district profiled, Southern Tioga in north-central Pennsylvania, is emblematic of our nation's hypocrisy around this issue. Nearly 60% of students in the eight grade are overweight, and 25% qualify as obese, but the schools serve funnel cakes and pizza for breakfast and some students take phys ed for only half the year.

So what's your solution? Any experience with obesity report cards? Or tips on how to keep our 'tween girls eating well and staying active without prompting screams and slammed doors at our parental interference? If so, please share.

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