MONDAY, Aug. 9 (HealthDay News) -- Among middle-aged and older adults, having a large waist can significantly raise the risk for dying prematurely, new research indicates.

The association appears to apply to both men and women, the study authors noted. What's more, having a normal weight does not, in fact, protect against such risk if you carry any excess weight in your abdominal region.

"A larger waist size was found to be linked to a higher risk for dying from cardiovascular disease, respiratory disease and cancer at every measure of body mass index," noted study author Eric J. Jacobs, an epidemiologist with the American Cancer Society in Atlanta.

Jacobs and his colleagues report their findings in the Aug. 9/23 issue of the Archives of Internal Medicine.

The authors noted that having a large waist circumference has previously been linked to a higher risk for having a wide swath of health problems including diabetes and heart disease, independent of overall weight and body mass index (BMI). BMI is a measurement that takes into account a person's height and weight.

Some suggest that the linkage stems from the greater presence of fatty tissue around organs in the abdominal area that seems to go hand-in-hand with having a larger waist size.

To specifically explore a potential association between waist circumference and a generally higher risk for death, the team looked at data concerning about 48,500 men and 56,000 women who had participated in a large national cancer study. Jacobs pointed out that the sheer size of this group meant that the current study is one of the largest efforts ever launched to examine any linkage between waist size and mortality.

All of the patients were aged 50 or older, with an average age of between 67 and 69. Between 1992 and 1993, all had completed health questionnaires concerning their medical histories, while weight and waist size statistics were gathered in 1997.

Deaths among the participants were tracked up until the end of 2006. By that point, about 9,300 men and 5,300 women had passed away.

Irrespective of BMI, the researchers found that having a large waist did indeed appear to be associated with having a higher risk for death.

Men who had a waist size of 47 inches or more bore about a twofold higher risk for death compared to men with the lowest waist size, they noted. The same increased risk was observed among women with a waist size of 42 inches or more.

The higher risk linked to greater waist size held whether or not men and women were of normal overall weight, overweight or obese, Jacobs and his associates noted. However, women of normal weight who nonetheless carried excess weight in their waist area appeared to be most vulnerable to the large waist-death risk association.

On this later point, the authors said they were not yet able to explain the underlying cause for the higher risk such women seem to face. They nevertheless suggested that the findings could lead to a shift in national guidelines for all men and women with respect to cautionary recommendations that currently highlight health risks linked with being overweight or obese overall, rather than risks specifically linked to abdominal obesity.

"Even if your weight is considered normal for your height, keeping your waist size is important for your health," Jacobs said. "So if you notice your waist size increasing over time, it's time to start eating better and exercising more."

With respect to women, Connie Diekman, director of nutrition for Washington University in St. Louis, took a shot at pinpointing a potential contributing factor.

"It's not totally a surprise, because menopausal women tend to store body fat in the abdominal area," she noted. "Because without the estrogen, our curves shift. So, this study really shows what we've long seen with women's increased risk for heart disease in the postmenopausal years, and indicates that it's an overall increased risk of death because of body fat," she explained.

"And in general, the very important message here is that this study reaffirms the harm and the danger of looking like an apple as opposed to carrying your body fat like a pear," Diekman added. "It is about the body fat you carry, not necessarily the number on the scale. It's one more reminder that we've sort of accepted this is a part of aging, people get big around their middle. But just because it's the norm doesn't mean it's OK."

More information

For more on weight, waist size and health risks, visit the U.S. National Heart, Lung, and Blood Institute.