Everyone knows that obesity is unhealthy, but now a new study shows that being obese in midlife dramatically increases your risk of dying early.
"People who are overweight have a moderately increased risk of premature death, and people who are obese have a greatly increased risk of premature death," said lead researcher Dr. Michael Leitzmann, an investigator at the National Cancer Institute.
His report is published in the Aug. 24 issue of The New England Journal of Medicine.
In the study, Leitzmann's group collected data on 527,265 men and women who were 50 to 71 years old in 1995 and 1996. Over 10 years of follow-up, the researchers looked at the relationship of weight to the risk of dying.
Through 2005, there were 61,317 deaths among those in the study. Leitzmann's team found that people who were overweight when they were 50 had a 20 percent to 40 percent increased risk of dying prematurely. For those who were obese, the risk of premature death was two to three times that of normal-weight people. "That translates into a 200 to 300 percent increase in the risk of premature death," Leitzmann said.
The researchers did not look at specific causes of death, but Leitzmann said the primary causes of premature death in this group were heart disease and cancer.
The advice to reduce the risk of premature death is obvious. "People need to maintain a normal weight throughout adulthood and avoid developing excess weight," Leitzmann said. "And if you are overweight or obese, lose the excess weight."
One expert thinks this study highlights the risk of death from any weight gain.
"This study adds good and compelling evidence to our previous suspicion that being overweight is a risk factor for early death, not just being obese," said Dr. Tim E. Byers, a professor of preventive medicine at the University of Colorado School of Medicine and author of an accompanying commentary in the journal.
The advice is nothing new, Byers said. "Let's watch our weight, especially for us baby boomers who have seen our weight creep up by a pound or two a year," he said. "Let's turn that around, and take small steps to start losing weight."
Another expert agreed that most diseases that shorten life can be laid at obesity's door.
"We should not need another word to recognize obesity as one of the great public health threats of our time," said Dr. David L. Katz, director of the Prevention Research Center at Yale University School of Medicine. "While uncertainty may persist about exactly how many years obesity takes out of life, there is overwhelming consensus about the life obesity can take out of years."
Most diabetes is due to overweight, as is much cardiovascular disease. And obesity is a major contributor to cancer risk as well, Katz said.
Another expert has a simple message to extend your life.
"The bottom line is watch your waistline if longevity is what you seek," said Lona Sandon, a spokeswoman for the American Dietetic Association. "Just because you do not have high blood pressure, diabetes or high cholesterol, does not mean you get a free pass on carrying extra pounds. Adopting a healthy diet and adding physical activity to drop those extra pounds just may extend your life."
Nutrition.gov can tell you more about healthy eating.
SOURCES: Michael Leitzmann, M.D., Dr. P.H., investigator, National Cancer Institute, Bethesda, Md.; Tim E. Byers M.D., M.P.H., professor, University of Colorado School of Medicine, Denver; David L. Katz, M.D., M.P.H., associate professor, public health, and director, Prevention Research Center, Yale University School of Medicine, New Haven, Conn.; Lona Sandon, R.D., assistant professor, clinical nutrition, University of Texas Southwestern Medical Center, Dallas, and spokeswoman, American Dietetic Association; Aug. 24, 2006, New England Journal of Medicine