People who are extremely obese are twice as likely to injure themselves as those who weigh less, a new study shows.

Researchers compared injury rates in a large group of adults and found extremely obese adults reported the highest number of personal injuries.

For example, more than one out of four extremely obese men had injured themselves in the past year compared with less than one in five normal weight men.

Examples of extreme obesity are a 5-foot-9-inch man who weighs 235 pounds or more or a 5-foot-4-inch woman who weighs at least 205 pounds.

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Undeniable Link

Researchers say this is the first study to look at the risk of personal injury among different weight groups in the general population and suggests that obesity may make people more prone to personal injury.

"There is undeniably a link between obesity and injury risk in adults," states researcher Huiyun Xiang, a researcher at the Center for Injury Research and Policy at Ohio State University, in a news release.

"Efforts to promote optimal body weight may reduce not only the risk of chronic diseases, but also the risk of unintentional injuries," says Xiang.

Read WebMD's "Risk of Death for Obese May Be Declining"

More Weight, More Falls

Researchers surveyed more than 2,500 adults living in Colorado. They collected information on personal injuries reported in the previous year and body mass index (BMI, a measure of weight in relation to height used to indicate obesity).

The results showed that extremely obese men and women reported a much higher number of personal injuries compared with other weight groups. Overall, researchers estimated having a BMI over 35 doubled the risk of personal injury over the past year.

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Other findings include:

26 percent of extremely obese men reported injuries compared with 17 percent of normal weight men. Nearly 22 percent of extremely obese women reported injuries compared with 12 percent of normal weight women. The most common causes of nonfatal injuries among the obese were overexertion and falls. More than half of the injuries among extremely obese people occurred within the home; transportation areas, such as parking lots, ranked a distant second.

"Obesity may limit what a person can physically do," says Xiang. "People with such limitations are often at a higher risk for injury than healthy people."

The results of the study appear in the July issue of the American Journal of Preventive Medicine.

By Jennifer Warner, reviewed by Michael W. Smith, MD

SOURCES: Xiang, H. American Journal of Preventive Medicine, July 2005; vol 29: pp 41-45. News release, Ohio State University.