Special interests run with faulty obesity data
By Randal O’Toole
America’s obesity epidemic has reached crisis proportions, says the Centers for Disease Control (CDC). CDC data indicate that obesity rates—the percent of people who weigh more than 130 percent of their ideal body weight—have increased by 60 percent in the last nine years.
To cure us of our fat, nutritionists want government to regulate food advertising aimed at children, tax high-calorie foods, and subsidize nutritious low-calorie foods. They also urge people to sue McDonalds and other fat purveyors for forcing us to gain weight.
Naturally, special interest groups have jumped on the anti-fat bandwagon. Smart growth urban planners claim that suburbs and automobiles are a public health menace because they encourage people to drive rather than walk. They recommend a dose of high-density housing and auto-free downtowns.
“Unadulterated junk science” is junkscience.com publisher Stephen Milloy’s view of the obesity epidemic. He points out, the claims that Americans are getting fatter are based on telephone surveys asking people their heights and weights to determine body-mass index. None of the data was ever verified for accuracy.
The CDC admits people are likely to understate their weight and overstate their height in telephone interviews. But this only convinces them the epidemic is even worse than their data indicate. In fact, they admit that actual measurements of Americans found obesity at rates greater than any of their telephone surveys (about 22 percent compared with 20 percent in the latest phone survey).
Now let’s get this straight. Your telephone surveys are so inaccurate that you know they are wrong without even doing any statistical tests. But you want to base major changes in public policy on such faulty data?
Since the telephone survey data is getting closer to the actual measurements each year, we may be dealing not with an obesity epidemic but an honesty epidemic: people increasingly telling the truth when a perfect stranger asks them how much they weigh. 
Perhaps the interviewers are prodding the interviewees for more accurate answers so they can get bigger budgets for their agencies. Perhaps the media has invited overweight people out of the closet by convincing them that they are simply victims of the food industry—“You’re fat, who can you sue?” says ABC News.
The definition of obese itself is problematic because body-mass index (BMI) does not distinguish between body types or consider a person’s overall health condition. The CDC defines “obese” as having a BMI of 30 or more; “overweight” is 25 or more. To calculate BMI multiply your weight in pounds by 703 and divide by the square of your height in inches. 
When the current definition of obesity was adopted in 1998 Milloy wrote, “According to the new federal standard: 98 percent of the last year’s Green Bay Packers were ‘overweight;’ 59 percent were ‘obese.’” The Packers made it to the Super Bowl that year. 
Still, maybe people did get fatter in the 1990s. The reasons for this change are far from settled. One thing that is clearly true is that obesity has no proven connection to the suburbs. The data show that obesity is associated with low incomes. Hispanics and African-Americans are also much more likely to be obese than non-Hispanic whites. The populations associated with obesity tend to be concentrated in cities.
Anti-sprawl activists blame obesity on increases in driving. But the CDC and other agencies report that the physical activity American adults undertake has remained constant for decades. Attempts to promote walking by creating auto-free downtowns will simply kill downtown businesses. Eugene learned this the hard way, and recently decided to open its downtown pedestrian mall to cars.
Fatty, sweet, and salty foods taste good, and the food industry gives us what we like. This only proves how democratic the free market truly is. How much of these foods we eat is a matter of self-discipline (or, for children, parental discipline), not something we want government bureaucrats to dictate to us.
Randal O’Toole is senior economist at the Thoreau Institute in Bandon, Oregon, and an adjunct scholar to Cascade Policy Institute, a Portland, Oregon think tank. He is author of The Vanishing Automobile and Other Urban Myths.