Trying to maintain their weight helped low-income, overweight African American women stave off depression, researchers reported.

The researchers looked at the confluence of two debilitating health issues. Depression is among the most common and disabling mental health conditions in the United States, and nearly 15 percent of African-American women will experience major depression in their lifetimes. Additionally, depressed African-American adults are less likely to get treatment for depression than are white people. Obesity is also disproportionately prevalent among African-American women.

At the start of the study, about 20 percent of the 185 participants reported symptoms of moderate to severe depression. Among the group in the weight management program, that number fell to about 10 percent after a year and after 18 months. Among the control group, there was no change.

“This equates to an almost 50 percent reduction in the proportion of intervention participants with moderate to severe depression,” the Duke University researchers wrote in the study, published recently in the American Journal of Public Health.

“It is exciting that we improved depression among a population that is severely socioeconomically disadvantaged and has limited access to depression treatment,” the lead author, Dori Steinberg, a research scholar with the Duke Digital Health Science Center, said in a statement.

Half the women, drawn from community health centers in North Carolina, were enrolled in a weight management program that included counseling, education, health-goal setting and self-monitoring. That program, called the Shape Program, included no mention of mood. The other women received the usual care, which included newsletters covering various health issues and a brochure on healthy weights.

The women were ages 25 to 44, with a body mass index - a measure of weight compared with height - that put them in the overweight to obese category. Eight percent of them had less than a college degree, and most were employed, though nearly three-quarters reported an annual income below $30,000.

After a year, 62 percent of the women in the weight-gain prevention program were at or below their beginning weight, compared with 45 percent of the group of women who got the usual care. The results were similar at 18 months. At that point, 14 of the women in the usual care group and nine in the intervention group reported taking a depression medication.

Depression was assessed using a standard questionnaire, and the women’s heights and weights were taken by trained staff.

Other studies have shown that African-American women have a more difficult time losing weight than women in other groups; it’s not clear why, the researchers said. But Steinberg said differences in norms about weight and physical activity, as well as other stresses, may be partly at the heart of it.

“These higher occurrences may also have an impact on psychosocial outcomes such as depression,” Steinberg said. “So interventions that focus on behavioral weight control may present a useful opportunity to address both obesity and depression.”