New concerns about teen obesity

In this photo a teen's waist is measured as she takes part in her final session of a 20 month obesity prevention study. Nearly one-third of American teens are overweight. (AP Photo/M. Spencer Green)

by Rima Himelstein, M.D.

What forces are adding to the obesity epidemic in teens? Here are key ones:

  • Fast food:  80 percent of teens underestimated the calories in their fast-food meals; they guessed 800 calories when the calorie count was really almost double that: 1,500.
  • Screen time: One third of teens spend close to 40 hours on TV and the computer every week and about 7 percent spend more than 50 hours.
  • No gym: Less than half of 9th-grade students and less than a quarter of 12th-grade students have physical education.

How it all adds up: Fast food plus screen time minus gym class equals obesity. It is no wonder that over 18 percent of children and adolescents are obese and that over 30 percent end up being obese as adults.

Is your teen overweight? Do the new math: The Body Mass Index (BMI) - a number that compares a person’s weight and height, for a more accurate assessment of whether they’re at a healthy weight - is a good way to evaluate a teen’s weight status for health reasons. You’ll find an easy-to-use BMI calculator here. Just type in your child’s height and weight and you’ll get a BMI number. What does it mean? For kids and teens, age is also a factor in determining how healthy a given weight is, so use these BMI percentile charts to find out. Children and adolescents with a BMI greater than the 95th percentile are considered obese.

We already know a lot about obesity.  It has many causes and it has many health risks. Obese teens may experience bone and joint problems, sleep problems, hypertension, and type 2 diabetes. Even at a young age, they may have signs of metabolic syndrome:

  • High fasting glucose or insulin resistance (signs of pre-diabetes)
  • Low high-density lipoprotein ( the “good” type of cholesterol)
  • High triglycerides (fat in the blood)
  • Hypertension (high blood pressure)
  • Abdominal obesity (too much belly fat)

People with metabolic syndrome are three times more likely to have a heart attack or stroke and five times more likely to develop type 2 diabetes than other people.

New information: Now there is evidence that obesity and metabolic syndrome may lower teens’ arithmetic and spelling abilities, attention, and mental flexibility. Brain images have shown actual changes in the brain, including fewer of the neural “connections” involved with higher-level thinking.     

“Battle on” against obesity. Right here in Philadelphia the battle is on. Food Fit Philly has a link to a list of more than 50 local farmers’ markets—including those that accept food stamps and vouchers—and a list of Philadelphia Public Schools that participate in the Get Healthy Philly program.

In your home, join in the fight against obesity:

Just say “yes”…

  • Avoid having foods and drinks that you will have to say “no” to, like candy, chips and soda.
  • Have healthy snacks in the kitchen instead, like fresh fruits and veggies. 

Move it …

  • Start exercise at 10 minutes a day and work up to the American Academy of Pediatrics’ recommendations of one hour 5 days a week.
  • Get your kids into after-school sports or dancing – they won’t even realize they’re exercising!
  • Limit TV, texting and computer to less than two hours a day.

Team work ... 

  • If you and your teen both have weight issues think about joining Weight Watchers together
  • Join a gym (some health insurance plans give discounts) or do some laps around a nearby track.      

 “5 over 6” ... 

  • Losing just 5–10 percent of current weight over 6 months can lower the risk for heart disease and other conditions.

Raise your voice …

  • Get involved in your school board to push for changes in the nutrition and physical education programs in your child’s school.
  • Don’t stop there!

Remember, you are not alone. Your teen’s doctor is on your team and wants to help you prevent the complications of obesity. 

Rima Himelstein, M.D., is a Crozer-Keystone Health System pediatrician and adolescent medicine specialist.