A new CDC study suggests that Americans may have reached the limits of human obesity.
Americans, at least as a group, may have reached their peak of obesity, according to data the Centers for Disease Control and Prevention released Wednesday.
The numbers indicate that obesity rates have remained constant for at least five years among men and for closer to 10 years among women and children — long enough for experts to say the percentage of very overweight people has leveled off. But the percentages have topped out at very high numbers. Nearly 34 percent of adults are obese, more than double the percentage 30 years ago. The share of obese children tripled during that time, to 17 percent.
“Right now we’ve halted the progress of the obesity epidemic,” said Dr. William H. Dietz, director of the division of nutrition, physical activity and obesity at the disease control centers. “The data are really promising. “That said, I don’t think we have in place the kind of policy or environmental changes needed to reverse this epidemic just yet.”
Dr. Dietz said the data probably reflected increased awareness of the obesity problem, especially among women, “who buy food, prepare it and see it, and they’re making changes for themselves that they’re also making for their kids.” He also cited a reduction in “less healthful foods” at school.
Some experts, though, were not optimistic that the leveling off was a result of improved eating and exercise habits. “Until we see rates improving, not just staying the same, we can’t have any confidence that our lifestyle has improved,” said Dr. David Ludwig, director of the Optimal Weight for Life Program at Children’s Hospital Boston.
Dr. Ludwig said the plateau might just suggest that “we’ve reached a biological limit” to how obese people could get. When people eat more, he said, at first they gain weight; then a growing share of the calories go “into maintaining and moving around that excess tissue,” he continued, so that “a population doesn’t keep getting heavier and heavier indefinitely.” Furthermore, Dr. Ludwig said, “it could be that most of the people who are genetically susceptible, or susceptible for psychological or behavioral reasons, have already become obese.”
Despite the enormous attention we’ve paid to the issue in recent decades, we’re at our infancy in understanding the physiology of fat. While there’s no doubt that the combination of plentiful, cheap food; processed foods; and a sedentary lifestyle are the chief contributing factors to America’s obesity epidemic, there are all manner of physiological ones that we’re only beginning to understand.
Beyond that, the study is based on BMI, which many of us think highly suspect.
The numbers, published in The Journal of the American Medical Association, are based on national surveys that record heights and weights of a representative sample of Americans. People are considered obese if their body mass index — a ratio of height to weight — is 30 or greater. Someone five and a half feet tall is obese at 186 pounds; a six-foot person is obese at 221 pounds.
At a little over 6’1″ and 220 pounds, I’m right at the borderline between overweight and obese. Then again, I’m middle aged and out of shape. But it’s a good thing the current BMI charts weren’t around when I was a 185 pound ROTC cadet running 5 miles a day and in the best shape of my life — I’d have been on the border of normal and overweight.
Many of us could stand to eat better and exercise more. And too many among us are morbidly obese, carrying around so much extra fat that their health is in jeopardy. But we’re also wildly overstating the “epidemic” with bogus statistical measures.
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Yeah, that is the great problem with BMI, it does not account for composition of the body mass. When I was a high school senior, I was 5’11,& 193lbs. I could bench press more than twice my body weight and run 3 miles in 18 minutes (while cursing my coach for making us run.) According to BMI, my 32 inch waist self was significantly overweight instead of being a high school athlete who had spent way too much time in the weight room getting ready for the season.
A combination of BMI, and waist line measurement would probably produce a much more accurate (and still fairly cheap) metric.
All I need to do is look in my high school yearbook and then look on the grounds of any high school today to recognize that Americans have gotten fatter over the years. However, I can also see differences between how fat people typically are in say, St. Louis, compared to how fat they are in Chicago.
I think there are any number of reasons for the phenomenon including sedentary lifestyle, diet, changing ethnic makeup, and Lord knows what all else.
However, I do wonder about something. Should the median BMI in the United States and the median BMI in China be the same and why?
BMI is a joke. Waist measurement wouldn’t be much better. My race tends to have smaller waistline than some others. Too much variance.
According to BMI, half the players in the NHL are obese, and most of the NBA is overweight. That tells you all you need to know about it. Studies based upon BMI aren’t worth the time it takes to read them.
The best easy measurement is the waist/hip ratio … under .90 for men, under .80 for women has a good correlation with good health.
I’m interpreting the title of this post as a personal challenge.
BMI is brutal to women-especially if they are muscular.
Personally, I think it would be nice if there was a simple way to determine fitness, rather than do a few measurements and plug in a height and weight and decide somebody is obese, but there isn’t.
I do see a lot more overweight kids in schools compared to when I was a kid, but then when I was in school we had recess two times a day and gym every day. Now kids are lucky if they have gym once a week and recess at all.
I also think parents are more overprotective and where I would have spent all day running around and playing with friends, kids now tend to stay inside and play video games or do other sedentary activities.
It’s one thing to be down on BMI(*), it’s another to treat it as a get out of jail free card.
* – notice that BMI is like IQ? It is a compression of a multidimensional quality onto a simple linear scale. IQ is only rudely “smarts.” BMI is only rudely “fatness.” I wonder though how many BMI haters are IQ lovers?
Sounds like a challenge!
It sounds like the waist/hip ratio is a better measurement. I have little experience with it or heard any opposing opinion so will hold my judgment. We certainly need something better than the BMI.