Small Incentives Improve Weight Loss in Women From Disadvantaged Backgrounds.

Introduction: Women from lower-income backgrounds have the highest rates of obesity. Thus, effective programs for this high-risk population are urgently needed. Evidence suggests that adding financial incentives to treatment helps to engage and promote health behavior change in lower-income populations; however, this has never been tested in women for obesity treatment. The purpose of this study was to examine whether adding small financial incentives to Internet weight loss treatment yields better weight loss outcomes in women from lower-income backgrounds compared with the same treatment without incentives. Weight losses in lower-versus higher-income women were also compared.

Methods: Data were pooled from two randomized trials in which women (N=264) received either Internet behavioral weight loss treatment (IBWL) or IBWL plus incentives (IBWL+$). Weight was objectively assessed. Data were collected and analyzed from 2011 to 2017.

Results: Women from lower-income backgrounds had significantly better weight loss outcomes in IBWL+$ compared with IBWL alone (6.4 [SD=4.9%] vs 2.6 [SD=4.6%], p=0.01). Moreover, a greater percentage achieved a ≥5% weight loss in IBWL+$ vs IBWL alone (52.6% vs 38.1%, p=0.01). Interestingly, the comparison between lower-income versus higher-income groups showed that, in IBWL alone, women with lower income achieved significantly poorer weight losses (3.4 [SD=4.2%] vs 4.9 [SD=4.0%], p=0.03). By contrast, in IBWL+$, weight loss outcomes did not differ by income status (5.0 [SD=5.6%] vs 5.3 [SD=3.8%], p=0.80), and a similar percentage of lower- versus higher-income women achieved a ≥5% weight loss (52.6% vs 53.8%, p=0.93).

Conclusions: An Internet behavioral weight loss program plus financial incentives may be an effective strategy to promote excellent weight losses in women with lower income, thereby enhancing equity in treatment outcomes in a vulnerable, high-risk population. These data also provide important evidence to support federally funded incentive initiatives for lower-income, underserved populations.