Report: Obesity Shortens Lifespan For Young Adults

It is no secret that people who are obese are not in perfect health. But that excess weight might be costing people in the long run.

A study released Monday found that being overweight at age 40 can shorten your life by three to seven years, but now a new, much larger report, suggests that being overweight in your 20s puts you at an even great risk of dying early.

Johns Hopkins University researchers studied years of federal health survey data on tens of thousands of people, focused on those with a body mass index of more than 24.

BMI is a calculation based on weight and height. Higher than 24 is considered overweight and higher than 30 is considered obese.

The date showed that people with a BMI over 45, or severely obese people, could expect their lives to be significantly shorter, especially if those people are young, around 20 years old. A severely obese young black woman could expect to lose four or five years of life, while an obese young white woman could expect to lose five or eight years.

But the findings regarding men surprised even the researchers. A severely obese young white man could expect to lose 12 years of life, while a young black man could expect to lose up to 20 years of life if he is severely obese.

"To see that years of life lost could be on the order of 12 to 20 years is quite astounding," researcher Dr. David Allison said.

The optimal BMI -- that associated with the greatest longevity -- was found to be about 23 to 25 for whites and 23 to 30 for blacks.

Researchers suspect the apparent race difference was due to limitations of the study. But they said that they hope the study will help motivate Americans, both young and old, to make weight loss a serious New Year's resolution.

"If they can think in terms of how many more years they would live if they were thin or normal weight versus obese, that may be more directly relevant, and may have more impact on them," Allison said.

In an accompanying editorial, researchers from Brigham and Women's Hospital in Boston underscored the obesity epidemic in the United States.

"Currently, two in three U.S. adults are classified as overweight or obese, compared with fewer than one in four in the early 1960s," they wrote.

A person who is 5 feet 4 inches and weighs 262 pounds would have a BMI of 45, while a person who is 6 feet tall and weighs 332 pound would have a BMI of 45. To have a BMI of 25, a 5-feet-4-inch person would need to weigh 145 pounds, and a 6-foot person would need to weigh 184 pounds.

Calculate your BMI.

Additional Resources:

National Heart, Lung, and Blood
Journal of the American Medical Association