If waistline trends continue unchanged, Obesity could soon reduce the average American’s life expectancy by up to 5 years, according to a report in The New England Journal of Medicine released Tuesday.

“It’s conceivable, it’s plausible,” study author Dr. David B. Allison, based at the University of Alabama at Birmingham, told Reuters Health. He explained that obesity shortens life expectancy primarily by increasing the risk of Diabetes, Heart disease and some cancers.

People at younger ages are now more obese than they were in previous generations, Allison said. Since people who are obese as children are more likely to be obese as adults, this means that, in future decades, the rate of Obesity among adults will likely increase, he explained.

This will in turn increase the rate of obesity-related diseases, shortening the average U.S. adult’s life by between 2 and 5 years, noted the researcher. However, he cautioned that these estimates are just that - estimates. If obesity trends change, so will the predictions.

“It could be that our predictions will be wrong,” Allison said. “We hope they will be wrong.”

In the report, Allison and his team note that the average life expectancy has slowly increased over the past 1,000 years.

However, within the last 20 years, the rate of obesity has climbed by 50 percent per decade, with the largest increases in children and minorities. Now, two thirds of all U.S. adults are overweight or obese, and obesity causes about 300,000 deaths every year.

The lifetime rate of diabetes among Americans has now risen to between 30 and 40 percent, Allison and his team report, largely due to obesity. Diabetes shortens life by an average of 13 years.

Based on the current situation, Allison and his team estimate that obesity is now cutting the average American lifespan by 4 to 9 months. And if trends continue, life expectancy could fall by an additional 2 to 5 years, or more, they note.

Allison noted that these trends could change if researchers find ways of extending life expectancy, perhaps through cures for cancer. Alternatively, people could live longer lives if society improves how it prevents and treats obesity or minimizes the consequences of obesity. “We’ve made progress, but progress is slow,” he said.

In an accompanying editorial, Dr. Samuel H. Preston points out that history shows Americans are capable of modifying their behavior in positive ways.

In recent years, the rates of Smoking, High Cholesterol and fatal accidents from drunk driving have all markedly decreased, largely the result of national awareness campaigns, Preston, of the University of Pennsylvania in Philadelphia, notes.

“The time has come to consider another major campaign,” he writes, to educate people about the impact obesity has on society.

SOURCE: The New England Journal of Medicine, March 17, 2005.

Provided by ArmMed Media
Revision date: July 3, 2011
Last revised: by Dave R. Roger, M.D.