Predict Cardiovascular Risk
If you want to determine your risk for cardiovascular disease, maybe
you should throw out your scale and grab the measuring tape.
A study appearing in a recent
issue of the American Journal of Clinical Nutrition suggests
waist circumference is more strongly associated with cardiovascular
risk factors than body mass index (BMI).
"There's been some
research that shows that it may not be the total amount of fat in
your body but where it is stored. In other words, fat distribution,"
says Stanley Heshka, a co-author of the study and a research associate
at the New York Obesity Research Center at St. Luke's Roosevelt
Hospital in New York City.
Body mass index (the measure
of body fat based on height and weight) is the most widely used
gauge to tell if adults are overweight or obese. The problem is
that it doesn't take into account the wide range of fat distribution
found in people.
Meanwhile, various studies
have found body fat distribution is a better predictor for many
In the new study, the researchers
looked at information on white men and women gathered for NHANES
III, the National Health and Nutrition Examination Survey, which
collected data on the health and nutrition of 9,019 Americans. Then
the researchers correlated BMI values of 25 and 30 (which indicate
overweight and obese, respectively) with cardiovascular and diabetes
risk factors. They set out to determine what waist circumferences
have the same degree of risk for cardiovascular disease and diabetes
as the BMI guidelines.
To minimize the risk of
heart disease, men should not go above a 35-inch waist and women
should not go above 33 inches, Heshka says. Men whose waists are
39 inches or more and women whose waists are 37 inches or more should
lose weight -- and inches, he says.
Though the study data involved
exquisitely precise measurements (taken just above the top of the
hip bone and at the end of a normal exhalation), regular folks don't
need to be quite that exact.
If you come close to the
recommended cutoff points, though, you need to take them seriously,
The researchers are still
working to figure out why girth may be a better predictor of risk
for cardiovascular disease. It may be because the amount of fat
around the waist reflects more fat inside the abdominal cavity,
something that has been associated with coronary vascular disease,
Some people have hypothesized
that the fat drains into the portal vein and is then distributed
to areas most sensitive to the development of cardiovascular disease.
"No one really knows
how the fat works," Heshka says.
Heshka is quick to add
that waist circumference alone may not be the best measure to determine
cardiovascular disease risk.
Heshka and other researchers
are now trying to see what combination of measures (for example,
height, weight, waist circumference, body frame size
) are the
best predictors for the development of cardiovascular disease.
"We may find that
waist circumference and BMI in combination have an even stronger
association," Heshka says. "That's what the goal is now:
To find optimal predictors so we can find those people at risk."
More data is also needed
to confirm that people with large waists are also the ones who eventually
develop cardiovascular disease.
What To Do
To learn more about cardiovascular
disease, visit the U.S. Centers
for Disease Control and Prevention (CDC). To calculate your
body mass index, visit this
Reference Source 101