There are many possible reasons why the United States is not on this list. It may not have been one of the countries selected by the surveyors. Also, the United States may not collect information on citizens’ weights and heights, without which it would be impossible to calculate their BMI. Another possibility is that the survey relied on self-reporting and that people intentionally or unintentionally underestimated their weight.
Estimates of the number of American adults who are overweight range up to two-thirds and as many as one-third may be obese (defined as having more than 30 per cent of body weight as fat). According to the mortality statistics, obesity killed 2,989 Americans in the year 2000, more than the number in the next eight highest countries combined.