They were also more likely to have their blood pressure under control up to two years out, researchers reported this week.

The participants were largely minorities and poor -- representing the Americans most affected by obesity and obesity-related health conditions, such as diabetes and heart disease, and some of the hardest to reach with prevention efforts.

In part because of those demographics, the new report is "encouraging," said Sara Bleich, an obesity researcher from the Johns Hopkins Bloomberg School of Public Health in Baltimore who wasn't involved in the new study.

"Typically what happens (in weight-management programs) is there's a lot of initial weight loss, and people gain it back pretty quickly," she told Reuters Health.

"A real positive to (this study) is the fact that we are seeing sustained weight loss, even though it is modest. That sort of sustained weight loss has the potential to reverse or alleviate a whole host of health problems."

The trial was conducted at three Boston community health centers. Close to 400 adults who were obese and being treated for high blood pressure were randomly assigned to get their usual care -- including a healthy weight booklet -- or to go through a goal-setting weight management program.

In the program, participants set small objectives for behavior changes, such as limiting TV watching, walking a certain amount each day and not drinking sugar-sweetened beverages. They received regular calls from community health educators over the two-year study to discuss their goals and progress, and were able to get feedback on a website or through "robocalls."

People in the weight management group also saw their primary care doctors once to discuss weight-related behavior changes and were invited to optional monthly group support sessions at the community health center.

More than 80 percent of the participants were black or Hispanic and the majority didn't have more than a high school degree or household income above $25,000. They were in their mid-fifties, on average, and started the study with an average weight of 220 pounds.

Gary Bennett, the study's lead author from Duke University in Durham, North Carolina, said the program was unique because it was based in a primary care setting and personalized to each participant -- rather than prescribing generic calorie limits or exercise recommendations for everyone.

Two years after the start of the study, the weight management group had lost slightly more weight than their usual-care peer group: 3.4 pounds versus 1.1 pounds, on average, according to findings published in the Archives of Internal Medicine.

"They didn't lose very large amounts of weight, but the weight that they lost, they kept off," Bennett told Reuters Health. He said more "clinically significant" than losing a few pounds were the blood pressure changes seen in participants.

Members of the intervention group had smaller increases in systolic blood pressure over time, and by two years out 65 percent of those participants had their blood pressure under control, compared to 58 percent of the comparison group.

Because the program mostly relied on community health educators instead of doctors, it could be feasible without tons of funding in the real world, researchers said.

Though Bennett's team is still working on a formal cost analysis, he said the program is "inexpensive enough I think that health centers (and) other primary care locations could adopt it themselves and offer it free or at very low cost to individuals."

Bleich worried what would happen after the goal-setting and phone check-ins ended, however. As in other studies of weight-loss interventions, "Once the intervention ends, it's likely that people's weight will creep back up," she said.

"If those resources drop off, then I think the weight gain's inevitable."

Still, both she and Bennett had an optimistic take on the findings. While it's very difficult to help people lose weight, preventing them from gaining weight is also important for warding off weight-related chronic conditions, Bennett said -- and this program did that, with a "simple enough" approach.

"Adopting a couple of…very small changes can have effects in the long term," he said. "It may not cause (patients) to lose weight, but it may help keep weight gain at bay."

SOURCE: Archives of Internal Medicine, online March 12, 2012.

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