Want to be even more depressed about fat kids?

Childhood obesity.  It’s a problem.  Kids, through no fault of their own (please tell me how much “self-control” you can expect a 5 year old to have in the face of Coke and Cheetos) find themselves with increased LIFELONG odds of developing diabetes, coronary heart disease, hypertension, nonalcoholic fatty liver disease, depression, and sleep apnea (just to name a few).

You know what makes it even worse?

The way overweight and obesity are classified for children.

Kids don’t have the same basic height to weight relationship adults do.  Therefore, BMI isn’t the best choice for kids.  BMI is a simple relationship of mass to height (kg/m^2).  Kids get pudgy, then the spread out, then they gain weight again, etc.  Their growth isn’t linear; it follows a sigmoid pattern.  Their BMIs fluctuate wildly just based on healthy growth and development.

Instead, overweight and obesity in children is based on what percentile of weight they fall into for their height and age.  Kids in the 85th-95th percentiles are classified as overweight, and kids above the 95th percentile are considered obese.

Of course, those percentiles have to refer to some baseline.  If not, exactly 5% of kids would be obese and 10% overweight every year.  However, about 32% of American kids are overweight or obese, and 17% of those are obese.  That means in relation to the children in the reference year, almost 1/3 of today’s kids would have been in the 85th percentile or above for weight (i.e our top 32% weigh at least as much as the top 15% used to).

So what data does the government use to determine overweight and obesity in kids?  Data from the 50s or 60s before the obesity epidemic struck?  That would certainly paint a bleak picture.  About twice as many overweight kids, and more than three times as many obese kids as there were in a time when kids were lean and active.

Nope.  Not the 50s or 60s.  It’s much bleaker than that.  The data used:  NHANES II.  In other words, DATA FROM 2004!!!!  When the obesity epidemic had already been brewing for over two decades!  There are more than twice as many fat kids as there were NINE years ago, and more than three times as many really fat kids!

I’m not the type to use all caps and multiple exclamation points very often, so when I do, it’s because I’m pretty riled up about something.  Learning this today probably marked my recent low point for faith in the human race.  Seriously.  Kids are at the mercy of their parents to keep them from getting ginormous, and an alarming number of parents are dropping the ball.

And yes, I’m putting the blame totally on the parents.  Kids have almost no say in anything that goes on in their life.  You might counter and say, “but kids are choosing to stay inside and play video games instead of playing sports outside.”  While that’s true, there’s not much evidence at all that physical activity affects weight and body composition very much until adolescence.  The only other major contributor to caloric balance is food intake.  I’d almost consider it child abuse when parents make available a ton of crap and let their kids eat themselves into long-term health consequences before they’re in middle school.

Anyway, that’s the end of my rant for this evening.  Do with it what you will.  I’m not a purveyor of parenting advice, but I do know that making healthy choices for kids affects them in the long-run.

It’s not quite as cute when you keep in mind that he’ll probably be on statins when he’s 30.


  1. I’m the parent of a fifteen-year-old. It wasn’t TOO long ago that I was a teen myself, but I’m amazed at how much culture has changed, and how these changes facilitate a sedentary lifestyle. My son is pretty fit, and last year he asked to start training with me in the gym. I’m lucky that I don’t have to worry about his health.

    However, his peers really do spend all of their time at home playing video games; none of these parents seem to be interested in getting their kids out of the house (which frankly boggles my mind). So when my son’s hanging out with friends, it’s Call of Duty and Cheetos, not roaming around the neighborhood or pickup basketball in the park. I think this is closely related to the “helicopter parent” phenomenon; the preponderance of parents won’t let their kids out of their sight, so the children just stay at home and get fat.

    1. Physical activity is important. I want kids to be active, but I also don’t think forcing the issue is good either. If they don’t enjoy it, making them do something they dislike will only make harder for them to enjoy it later in life. I agree with what Greg said. Parents need to own the responsibilities that cone with children. If you have them, take care of them! It isn’t that hard to have good snacks around and have healthy meals. It takes more effort, but that should be expected. Parents are lazy and don’t prioritize being healthy.

      1. That’s a good point about forced physical activity. I don’t have the studies on hand at the moment, but research seems to suggest that when parents force activity on their children, those kids tend to be less active later in life than kids who (though they were less active in childhood) were not forced to engage in exercise.

    2. I definitely agree. Starting the habit of being active is good for children. However, the point I was making was that until adolescence, activity isn’t a very strong predictor of weight or body composition. Trade the Cheetos with carrot sticks and you probably wind up with normal weight (though still lazy) kids.

  2. But Greg, you’re obese according to BMI! A better measurement would be body fat percentage. I’m borderline overweight at around 10% body fat and still look quite lanky. Someone at 30% body fat at my weight would look very very different.

    1. I agree 100% on a person-to-person basis. However, BMI is actually quite good for evaluating health risks across an entire population. It’s supposed to track with bodyfat percentages and does so quite well. Less than a tenth of a percent of people are obese and fall within a healthy bodyfat range, so it doesn’t make much sense to use a statistical measure just because of outliers like us. Ya know what I mean?

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