Numbers Reveal Gravity of Obesity Problem

Jan. 4 -- Now may be a good time to remind ourselves that many of us are beginning to physically resemble the new palindromic year, 2002: wide, round, and symmetric-looking. A little arithmetic helps in assessing how heavy we've become.

American children, in particular, are fat and rapidly getting fatter. Furthermore, their fatness will likely lead to innumerable health problems as they age. These are the conclusions of a large study published last month in the Journal of the American Medical Association by Richard Strauss, a pediatrician at the Robert Wood Johnson Medical School in New Brunswick, N.J.

Oddly, the report also found that over 20 percent of minority children and approximately 12 percent of white children were at or above the 95th percentile in body mass (the definition of the body mass index, or BMI, appears below) and hence considered obese.

Fat Children and Bulging Percentiles

Given the children's heft, it is particularly intriguing to imagine how 20 percent of them could be shoehorned into 5 percent of the distribution of body mass (or any other measure). That is, how is it that fully 20 percent of the minority children in the study weighed more than 95 percent of minority children? (Similarly, 12 percent of white children in the study weighed more than 95 percent of white children.) This seems to be a variant of the situation in Lake Wobegon where all the children are above average.

The mini-mystery about the maxi-children is resolved when one realizes that the percentile rankings were based on body mass charts compiled decades ago. Twenty percent of today's minority children are as heavy as the heaviest 5 percent of minority children were between 1960 and 1980 (12 percent for white children).

Movement to Stop the Weight Gain

Resolving this seeming paradox underscores how serious the problem of childhood obesity is. Among the causes for its dramatic increase are the prevalence of junk food, lack of exercise, and excessive television and video watching. (Poverty is also a factor. Happily, the Segway Human Transporter is prohibitively expensive, but the new X-box promises countless hours of immobility.)