A woman tests her blood sugar level as part of her management of diabetes. Modest weight loss won't lower the risk for a heart attack or stroke in people with diabetes, according to a new study.(Photo: David Proeber, AP)
People with type 2 diabetes often are encouraged to lose weight to
improve their health, but a puzzling new study may have some questioning
A recent study showed that obese people with
diabetes who lost a modest amount of weight didn't lower their risk of
having a heart attack or stroke, but the weight loss did help improve
many other health factors.
"While we did not show a benefit of
modest weight loss for cardiovascular events, we did show the benefits
of weight loss for improving depression, quality of life, sleep apnea,
incontinence, fitness, physical function and blood sugar control," says
Rena Wing, a professor of psychiatry and human behavior at Brown
University and chairman of the Look AHEAD (Action for Health in
Diabetes) study. The research was financed by the National Institutes of
In diabetes - a disease spotlighted in November during
American Diabetes Month - the body does not make enough of the hormone
insulin, or it doesn't use it properly. Insulin helps glucose (sugar)
get into cells, where it is used for energy. If there's an insulin
problem, sugar builds up in the blood, damaging nerves and blood
vessels. There are two major forms: type 1 and type 2, which accounts
for 90% to 95% of diabetes.
Diabetes can lead to heart disease,
stroke, kidney failure, foot and leg amputations and blindness. Almost
26 million children and adults (8.3% of the population) in the United
States have diabetes.
the study, researchers at 16 centers around the country worked with
5,145 obese people with type 2 diabetes. Their average starting weight
was about 200 pounds. The study was designed to see whether weight loss
reduced the risk of heart attacks and strokes.
Half of the
participants were assigned to an intensive diet and exercise program.
They attended individual and group meetings where they were taught
strategies for weight loss by cutting calories and increasing physical
activity. They used some meal replacements during the weight-loss and
maintenance phases of the program.
The other half received a
general program of diabetes education several times a year. All
participants continued to follow the medical advice of their physician.
Those in the diet group lost about 8% of their starting weight (about
16 pounds) in the first year and maintained nearly 5% (about 10 pounds)
of that loss. Participants in the diabetes education group lost about 1%
(2 pounds) of their starting weight and kept it off. Everyone was
tracked for up to 11 years.
After four years, the findings showed
that those in the diet-and-exercise group improved their hemoglobin A1C
readings (which looks at a person's average blood sugar levels for the
past three months), fitness, systolic (top number) blood pressure and
HDL (good) cholesterol more than those in the diabetes education group.
The diet-and-exercise group also required less medication to control the
diabetes, Wing says.
Participants in the diabetes education
group, however, had better LDL (bad) cholesterol at year four, possibly
because more of them were taking cholesterol-lowering drugs, she says.
was no difference between the two groups in the incidence of heart
attacks and strokes, but the incidence was low in both groups, Wing
says. "The fact that they had lower rates of cardiovascular disease than
we expected probably reflects improvements in medical management of
Physicians today are working harder to make sure the
patient has good blood sugar control and has good blood pressure and
cholesterol levels, she says. "There has been much more intensive
medical management of people with diabetes to prevent heart disease."
says researchers will continue to monitor the study participants to
see whether their weight loss lowered their heart attacks later in their
lives and to assess other possible long-term benefits of weight loss.
study provides important information, but we don't know from this study
whether larger weight loss would have better impact, and we don't know
if these weight losses would have decreased the risk of heart attacks
and strokes in people without diabetes," she says.
executive director of the Anschutz Health and Wellness Center at the
University of Colorado and the principal investigator at the study's
site in Denver, says the bottom line is still: "Losing weight is one of
the best things you can do for your health if you are overweight with
type 2 diabetes."
Thomas Wadden, director of the Center for Weight
and Eating Disorders at the University of Pennsylvania's Perelman
School of Medicine, adds: "Regardless of its effects on heart disease,
modest weight loss and increased physical activity improve multiple
aspects of health and well-being in overweight individuals with and
without diabetes. Let's not throw out the baby with the bathwater."
Sue Kirkman, senior vice president of medical affairs for the American
Diabetes Association, says the message is that there are lots of other
benefits for weight loss, such as needing fewer medications and better
quality of life, and "we know that weight loss helps prevent or delay
type 2 diabetes."
Facts about diabetes:
• Almost 26 million children and adults (8.3% of the U.S. population) in the United States have diabetes.
• 18.8 million people are diagnosed; an additional 7 million are undiagnosed.
• Another 79 million Americans have prediabetes and are at risk for developing type 2 diabetes.
• An estimated one in three Americans may develop diabetes by 2050 if something isn't done to reverse the trend.
Source: Centers for Disease Control and Prevention