A new study suggests extreme obesity can shorten an individual's life by up to 14 years, due to a higher risk of cancer, heart disease, stroke, diabetes, and kidney or liver diseases.
The National Cancer Institute's Cari Kitahara and her colleagues reviewed 20 studies conducted in the United States, Sweden and Australia. The participants were classified according to their body mass index (BMI): normal, overweight, obese, severely obese, and extremely or morbidly obese. One is considered "extremely obese" if his or her BMI is equal or greater than 40. According to the U.S. Centers for Disease Control and Prevention (CDC), 7.2 percent of the female population in the United States were extremely obese, while 4.2 percent of men were classified as such during the span of 2007 to 2008.
"While once a relatively uncommon condition, the prevalence of class III, or extreme, obesity is on the rise. In the United States, for example, six percent of adults are now classified as extremely obese, which, for a person of average height, is more than 100 pounds over the recommended range for normal weight," Kitahara said.
The researchers excluded individuals who smoked or had history of certain diseases in their evaluation of the risk of overall premature death from specific causes. They compared the data of 9,500 extremely obese participants to 304,000 normal-weighted participants.
After careful analysis, the researchers concluded extremely obese people have shorter life spans when compared to people of regular weight.
Analysts found extremely obese people mostly died due to heart disease, cancer and diabetes. People with BMI of 40-44.9 lived 6.5 fewer years, while those with BMI of 55-59.9 lived 14 years shorter compared to those with normal weight.
"Given our findings, it appears that class III obesity is increasing and may soon emerge as a major cause of early death in this and other countries worldwide," Patricia Hartge, senior author of the study from the Division of Cancer Epidemiology and Genetics, added.
The study was published in the July 8 issue of PLOS Medicine.
