Obesity Called A Public Health Crisis In U.S.

(for Australian Doctor)

 

Approximately 97 million people, more than half the adult population of the United States, are overweight, and more than one-fifth of the population is obese.  These statistics are derived from household-based surveys, which used the criteria of body-mass index (BMI) of 25 or more for overweight and 30 or more for obesity.  Done repeatedly since 1960, the surveys showed that national prevalence rates remained stable between 1960 and 1980, but increased sharply since that year, with the rate for overweight rising by 20% and that for obesity jumping 50%, according to data from the most recent survey completed in 1994.

 

Speaking at a conference on "Obesity: The Public Health Crisis" in Washington, D.C., Dr David Satcher, the U.S. Surgeon General, described overweight as an epidemic in the U.S. population and revealed that beginning in January 2000, rates of overweight will become one of the 10 leading indicators used to assess the overall health of the nation.

 

The public health epidemic can be attributed to several interacting causes, according to Janet Collins, Ph.D., of the Centers for Disease Control and Prevention (CDC).  Among these, the most important appear to be increased dietary intake, especially in the form of  "fast food", decreased physical activity, and increased levels of inactivity.  She and other speakers were careful to explain that the epidemic cannot simply be attributed to higher caloric intake, and that increased inactivity should be distinguished as a concept from decreased physical activity.  During recent decades the numbers of hours spent in sedentary activities, such as watching television, working at computers, and driving in cars has increased substantially. A number of studies have shown that weight loss consistently results from interventions that decrease time spent in inactivity, such as television watching, without specifically increasing physical activity or reducing intake.

 

Minority populations have been especially hard hit by the obesity epidemic, with significantly higher rates among non-whites and Hispanics than among non-Hispanic whites. Also women have shown a higher prevalence rate than men.  A number of scientists speaking at the conference agreed that genetic differences are a major factor, contributing as much as 50% to the problem. Biological differences related to inheritance and sex may both cause certain groups to be more vulnerable to the changes in diet and lifestyle that have occurred in recent decades.

 

Collins said that obesity has increased 100% among U.S. children and adolescents in the last 25 years. One quarter are presently considered overweight, and more than 10% are obese.  Obesity present in childhood has been reported to have a 70% likelihood of persisting into adult years.  And type II diabetes mellitus in children now accounts for 16% of all childhood diabetes, reflecting a five-fold rise in prevalence during the same period in which childhood obesity has increased.

 

Dr. Robert Rubin, Professor of Medicine at Georgetown University and former Assistant Secretary of Health, described the medical and economic consequences of obesity.  The condition is an important etiologic factor in cardiovascular disease, cancer, and many chronic diseases.  In monetary terms, as much as 70% of the costs of treating an obese patient for cardiovascular disease or diabetes may be attributable to his weight, as may 30% of all the direct medical costs of treating that patient.