Waist Size Predicts Heart Disease Danger
Large Waistline Measurement a Sign of Insulin Resistance in Men and Women
April 14, 2005 -- If you don't listen to your doctor, listen to your
By the time the tailor's tape says your waistline is larger than 39 inches,
you may already be on the
This holds true for both men and women, find Hans
Wahrenberg, MD, and colleagues at Sweden's Karolinska Institute.
"This is like an alarm warning that you are going into the risk
area," Wahrenberg tells WebMD.
Why? Wahrenberg's team finds that half of all men and women with waistlines
of one meter or more -- that's 39.37 inches or more in the U.S. -- already have
insulin resistance. But very few people with smaller waists have developed this
Wahrenberg and colleagues report their findings in the April 15 Online First
edition of the British Medical Journal.
Insulin Resistance: A Risk for Diabetes, Heart Disease
The cells in your body are powered by the sugar molecules called glucose. To
keep this powerful fuel from flooding cells' engines, your body uses a hormone
-- insulin -- to regulate glucose uptake. Insulin opens cells' gas caps so
glucose can flow in.
But cells sometimes stop responding to insulin. This is what doctors call
insulin resistance. When you have insulin resistance, your blood floods with
glucose, which increases your risk for diabetes. It also fills it with other
molecules that promote heart-clogging blood clots.
There are tests that gauge insulin resistance, but they are complicated,
cannot be done in an office, and are usually reserved for research purposes.
Now, Wahrenberg offers doctors and patients an easy rule of thumb for gauging
who likely has insulin resistance.
The researchers looked at data from 2,746 "healthy" volunteers aged
18 to 72, whose waistlines ranged from 25.6 to 59 inches. All underwent
complicated testing for insulin resistance.
"Insulin-resistance tests are positive in 50% of those who have a waist
circumference above 1 meter [39.37 inches]," Wahrenberg says. "There
are still obese people who are not insulin resistant. But if people have a
waistline less than 1 meter, there is very little chance they are insulin
Earlier studies have suggested that insulin resistance can be predicted
based on other clinical features. These features include body mass index (BMI),
weight, hip circumference, and waist-to-hip ratio. But Wahrenberg says waist
circumference alone predicts insulin resistance better than any of these other
features alone or in combination.
"We are astonished waist circumference is so good a predictor," he
says. "We had not expected it would have such good power."
The results also surprise Youfa Wang, MD, PhD, of the Center for Human
Nutrition at the Bloomberg School of Public Health at Johns Hopkins University.
Wang has studied ways to predict diabetes and heart disease.
"I am astonished," Wang tells WebMD. "It is quite encouraging
that waist circumference is a very good predictor of insulin sensitivity and a
good screening tool. It is very impressive that this can replace the other
measures such as BMI as predictors."