Wondering if you're going to develop diabetes in your lifetime?
Spend a minute on the bathroom scale: According to new research,
your weight can provide a good indication of your future
risk.
Nearly three out of four morbidly obese 18-year-old men,
for example, will develop type 2 diabetes in their lifetime.
And 35 percent of 18-year-old women who are simply overweight
will contract the disease.
"This is the first time we were able to collect the
type of data needed for these observations," said study
author Dr. K.M. Venkat Narayan, chief epidemiologist at
the U.S. Centers for Disease Control and Prevention. The
research "can help us to know where to focus our attention."
Narayan's report is one of several studies into diabetes
risk factors that are being released at the American Diabetes
Association's annual scientific sessions, in Washington,
D.C.
In the Narayan study, researchers examined the results
of a national survey of almost 800,000 U.S. adults completed
between 1997 and 2004. The researchers wanted to find out
how body mass index (BMI) -- a ratio of weight to height
-- translates into diabetes risk.
According to the study, an obese man with a BMI around
30 -- say, a 6-foot-tall man who weighs 225 pounds -- has
a 57 percent chance of developing type 2 diabetes. A woman
with the same BMI -- say, weighing 190 at 5-feet, 6-inches
-- has a 55 percent chance.
By contrast, just 20 percent and 17 percent of 18-year-old
men and women of normal weight, respectively, are expected
to develop type 2 diabetes, the study found.
"The message here is, compared to a person with normal
weight, a person who is overweight or obese at age 18 has
a substantially higher chance of developing diabetes during
his or her lifetime," Narayan said.
Among people aged 65 and older, "the additional risk
of being overweight added a bit of extra risk, but not so
much," Narayan said. "It's a very different situation
from an 18-year-old who's overweight."
But older people who are obese had a "substantially
higher" risk of type 2 diabetes than those who weighed
less, Narayan said.
Why are overweight people at risk of diabetes? The reasons
aren't clear, but they appear to have something to do with
how fat disrupts the ability of cells to work with the hormone
insulin, which helps convert blood sugar into energy for
the body, Narayan said.
An estimated 19 million Americans have type 2 diabetes,
and studies suggest that one-third of adults with the disease
don't even know they have it. If left untreated, the disease
can lead to complications such as heart disease, stroke,
blindness, kidney disease, nerve problems, and foot or limb
amputation.
Being overweight is thought to be a key risk factor for
the disease.
Dr. Robert J. Rushakoff, an associate clinical professor
of medicine at the University of California, San Francisco,
said the study findings are "alarming" but valuable
to doctors.
"Since prevention is so important, physicians and
other health-care providers can make use of these dramatic
numbers to talk to patients and try to start a move to better
diet and exercise," he said.
In another study released at the diabetes meeting, Swedish
researchers have linked three gene variants to type 2 diabetes.
People with two or more of the variations have the highest
risk of the disease. But, the researchers added, it's too
early to predict for sure if someone will develop the disease.
