Expansion Crests

Only so far you can go:

After 25 years of what health officials call an obesity epidemic, American adults finally may be getting a handle on the battle of the bulge, according to federal data released Wednesday.

The Centers for Disease Control and Prevention said 34.3% of adults -- or more than 72 million people -- were obese in 2005 and 2006. The figures were essentially unchanged from the previous two-year period for the first time since 1980.

...The report didn't weigh in on why Americans seem to be holding steady. Experts surmised that the government's incessant calls for people to slim down may be finally paying off. They added that membership in fitness clubs is on the rise, and prohibitions against artery-clogging trans fats in restaurants are gaining ground in the name of public health.

Others raised a more fundamental explanation.

Glenn Gaesser, an exercise physiologist at the University of Virginia and author of the iconoclastic book "Big Fat Lies," said there just may be metabolic limit to body weight.

Americans may have finally reached that point. "You can only get so fat," he said.