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DURHAM, N.C. – In the largest and longest study to date of
weight loss maintenance strategies, researchers at Duke
University Medical Center found that personal contact – and, to
a lesser extent, a computer-based support system – were helpful
in keeping weight off.

The results of the study appear in the March 12 issue of the
Journal of the American Medical Association.

"The results of this study send a strong signal to those who
seem to believe that obesity is such an intractable problem
that nothing can be done about it," says Dr. Laura Svetkey,
professor of medicine at Duke and the lead author of the study.
"Our research shows that is not true. A large majority of the
participants in the Weight Loss Management study lost weight
and kept weight off for two and one-half years."

Svetkey and researchers at four institutions around the
country studied 1685 overweight or obese adults who were being
treated for high blood pressure, high cholesterol, or both.
Scientists asked participants to increase their activity level,
reduce their calorie intake and follow the DASH diet (Dietary
Approaches to Stop Hypertension) for a period of six months.
The DASH diet emphasizes fruits, vegetables, low-fat dairy
products and whole grains, and has been proven to lower "bad"
cholesterol and blood pressure.

In the first phase of the study, participants attended 20
weekly group meetings with a trained interventionist who
coached them on making these lifestyle changes. Only
participants who lost at least nine pounds were admitted to a
second phase of the study; 61 percent met that goal, with
weight loss ranging from nine to 66 pounds.

In the second phase, 1032 participants were randomized to
one of three groups: a self-directed control group, where they
were left to their own devices to manage their weight; a
personal contact group, where they received monthly coaching
and support from a counselor assigned to them; or a
computer-based, weight loss maintenance program that offered
the same counseling that personal contact offered, but in a
virtual, interactive format.

More than 70 percent of the participants weighed less at the
end of the study than when they started. Those in the personal
contact group were the most successful, with 77 percent
maintaining some weight loss. The computer intervention group
had a 69 percent success rate and the self-directed group had
67 percent.

"In addition, 42 percent of the personal contact group was
able to maintain weight loss of at least 5 percent of their
starting weight, an amount of weight loss that has clear health
benefits," Svetkey said. "In the other groups, about 35 percent
were able to maintain this much weight loss."

Overall, however, the effects of the interventions were
modest. At the end of the study, the personal contact group had
regained 3.3 pounds less than the self-directed group. Those in
the computer-based support program fared almost as well – at
least for the first two years. After that point, the virtual
intervention lost its edge, and by the end of the study, their
efforts at maintaining weight loss were similar to those
enrolled in the self-directed control group.

But Svetkey, director of clinical research at the Sarah W.
Stedman Nutrition and Metabolism Center at Duke, points out
that even modest success paves the way to major victory.

"We didn't set out to cure obesity, but we did want to offer
participants a set of tools they could use to change their
lives," Svetkey said. It's not easy to counteract all the
forces around us that encourage us to overeat and be sedentary,
but we think this study moves us in the right direction."

Svetkey stresses that every pound lost can lower blood
pressure and risk of developing diabetes. "Our patients have
shown that under the right conditions, long-term weight control
is an achievable goal worth pursuing," says Svetkey. "It's also
important to understand that it's not necessary to reach a
normal weight to improve your health. The focus needs to be on
changing a lifestyle and sticking to it. Every pound lost
improves health."

The study was funded by the National Heart, Lung, and Blood
Institute. Svetkey says it its notable that, unlike most other
weight loss studies, the Weight Loss Management study included
a large number of African-American participants (38 percent)
and large n numbers of men and women. Studies show that obesity
is more prevalent among African-Americans and the consequences
of obesity are more serious for blacks than whites.

Researchers from Duke who contributed to the study include
Carmen Samuel-Hodge, Lillian Lien and Kathleen Aicher.
Additional work came from scientists at The Kaiser Permanente
Center for Health Research, Pennington Biomedical Research
Center and Johns Hopkins Medical Institutes.