BOSTON — While the senior market may be seen as growing and lucrative for the fitness industry, the effect of obesity in the young adult population on the nation's future healthcare costs begs the industry not to overlook this population.

Men and women who were overweight or obese in young adulthood and middle age have significantly higher Medicare costs in older age compared to their nonoverweight peers, according to a study in the December 8 issue of “Journal of the American Medical Association.”

Approximately 130 million U.S. adults are currently overweight or obese, defined as having a body mass index of 25 - 29.9, or 30 and greater, respectively. The proportion of U.S. adults aged 65 years and older is estimated to increase from 12 percent currently to 20 percent by 2050.

Obesity combined with this rising number of older persons in the United States are of concern to health care professionals, policymakers and the U.S. public. However, little is known about the relation of overweight or obesity in young adults to long-term medical care expenditures.

Martha L. Daviglus, M.D., Ph.D., from the Feinberg School of Medicine, Northwestern University, Chicago, and colleagues examined the relationship between BMI in young adulthood and middle age to Medicare spending at ages 65 years and older.

Between 1967 and 1973, BMIs and overall health were measured in 9,978 men (average age, 46 years) and 7,623 women (average age, 48 years) participating in the Chicago Heart Association Detection Project in Industry. Researchers then examined Medicare claims data for these participants from 1984 through 2002.

The researchers found that annual average Medicare charges for severely obese men were $6,192 more (84 percent higher) than for nonoverweight men. For severely obese women, annual average charges were $5,618 more (88 percent higher) than for nonoverweight women.

“Our findings demonstrate the adverse impact of high BMI in young adulthood and middle age (irrespective of changes in weight that may have occurred over the years) on future Medicare expenditures. With current trends of increasing overweight and obesity afflicting all age groups, urgent preventive measures are required not only to lessen the burden of disease and disability associated with excess weight but also to contain future health care costs incurred by the aging population,” the authors wrote.

About 130 million U.S. adults are currently overweight or obese, the study said.