Odds Favor Becoming Overweight During Lifetime

NEW YORK (Reuters Health) - If you aren't overweight now, you probably will be, according to data from the Framingham Heart Study, the ongoing look at the health of Americans in one Massachusetts community.

The latest analysis shows that the likelihood of a 30-year-old person being or ever becoming overweight is 74 percent for women and 92 percent for men. The corresponding risks for becoming very overweight (i.e., obese) were 39 percent and 48 percent.

Although overweight and obesity generate a lot of research and media attention, the short- and long-term risks of developing these problems were unknown, the study's authors note in the Annals of Internal Medicine.

The study included 4117 white men and women who were followed from 1971 to 2001. Overweight and obesity were defined as body mass indices (BMI) of at least 25 and 30, respectively.

BMI measures weight in relation to height. It's calculated as weight in kilograms, divided by the square of height in meters -- and a calculator can be found at http://www.cdc.gov/nccdphp/dnpa/bmi/calc-bmi.htm.

In the short term (4 years), between 14 percent and 19 percent of women became overweight, as did 26 percent to 30 percent of men, Dr. Ramachandran S. Vasan and colleagues report. The short-term rates of obesity were 5 to 7 percent for women and 7 to 9 percent for men.

In the long term (30 years), over 50 percent of subjects became overweight and more than 25 percent became obese. The risk of developing severe obesity (BMI of at least 35) was greater than 10 percent.

"The lifetime risk for overweight approaches that for high blood pressure and exceeds that described for most other chronic diseases," Vasan's team notes. "These estimates suggest that the future burden of obesity-associated chronic diseases may be substantial."

SOURCE: Annals of Internal Medicine, October 4, 2005.