The findings, reported in the medical journal Circulation, add to evidence that when it comes to health risks, overall weight is not as important as where a person carries the fat.
Past studies have found that "apple-shaped" people appear to be at particular risk of clogged arteries, high blood pressure and diabetes. Abdominal obesity has also been linked to certain cancers, such as kidney cancer and colon cancer.
In the new study, researchers at the National Institutes of Health and Harvard Medical School found that middle-aged and older women who were abdominally obese -- with a waistline of 35 inches or more -- were more likely than their thinner counterparts to die of heart disease or cancer during the study period.
Among the more than 44,000 U.S. women the researchers tracked over 16 years, abdominal obesity doubled the odds of dying from heart disease or stroke, compared with women whose waistlines were smaller than 28 inches.
When it came to the risk of cancer death, women with the largest waists had a 63 percent higher risk than women who were most trim around the middle.
What's more, the study found, the risks of a large waist were independent of a woman's overall body mass index (BMI), a measure of weight in relation to height. In fact, even among normal-weight women, those whose waistlines spanned 35 inches or more faced a greater risk of dying from heart disease or stroke.
The results highlight the importance of staying trim around the middle as we age, according to the researchers, led by Dr. Cuilin Zhang of the National Institute of Child Health and Human Development.
"Although maintaining a healthy weight should continue to be a cornerstone in the prevention of chronic diseases and premature death," Zhang and colleagues write, "it is equally important to maintain a healthy waist size and prevent abdominal obesity."
Excess abdominal fat is thought to be particularly unhealthy because of its metabolic effects. Too much fat in this area of the body appears to raise cholesterol levels, promote insulin resistance -- a precursor to type 2 diabetes -- and spur body-wide inflammation, which may contribute to heart disease and certain cancers.
SOURCE: Circulation, April 1, 2008.
Last Mod: 23 Nisan 2008, 12:45