About three-quarters of the obese Americans who participated in a telephone survey described their eating habits as healthy, and 40 percent said they engaged in vigorous exercise three or more times a week. Who are they kidding? Or is it possible they're telling it like it is?

Of the 11,000 participants, about 3,000 were obese or morbidly obese, 4,200 were overweight, 3,800 fell in the normal weight range, and 200 were underweight. In the general American population, approximately one-third are obese, while more than two-thirds are overweight.

Twenty-eight percent of the obese respondents did admit to indulging in two or more snacks a day, versus 24 percent of their normal-weight counterparts. Obese people indicated they were more likely to clean their plates, more likely to eat in restaurants and less likely to read nutritional labels on food than people of normal weight.

However, the relatively small margins of difference do not seem likely to explain very large differences in weight.

The researchers indicated skepticism over the survey results, speculating that many of the participants could be misleading themselves about what constitutes healthy eating and vigorous exercise.

There was apparently no objective way to assess whether they were in denial or not, however, since the survey did not include questions on exactly what foods -- or what quantities of food -- individuals were eating.

Differences in perception aside, it is clear that American lifestyles have changed in the past several decades in ways that would seem likely to contribute to weight problems in the general population.

Driving has become much more common than walking to destinations; the advance of high-technology means that jobs are increasingly sedentary; and the need for parents to have jobs outside the home means that more families are eating fast food and other convenience meals in place of more nutritious home-cooked fare.

However, if the survey respondents were providing an accurate description of their habits, it may be that the oft-repeated admonition to "eat right and exercise" is a sorely lacking prescription for solving the nation's obesity epidemic, and the health officials who persist in "blaming the victims" may be the ones who need a reality check.