Effectiveness of Monetary Incentives in Modifying Dietary Behavior: A Review of Randomized, Controlled Trials

Abstract

To review research evidence on the effectiveness of monetary incentives in modifying dietary behavior, we conducted a systematic review of randomized, controlled trials (RCTs) identified from electronic bibliographic databases and reference lists of retrieved relevant articles. Studies eligible for inclusion met the following criteria: RCT comparing a form of monetary incentive with a comparative intervention or control; incentives were a central component of the study intervention and their effect was able to be disaggregated from other intervention components; study participants were community-based; and outcome variables included anthropometric or dietary assessment measures. Data were extracted on study populations, setting, interventions, outcome variables, trial duration, and follow-up. Appraisal of trial methodological quality was undertaken based on comparability of baseline characteristics, randomization method, allocation concealment, blinding, follow-up, and use of intention-to-treat analysis. Four RCTs were identified as meeting the inclusion criteria. All four trials demonstrated a positive effect of monetary incentives on food purchases, food consumption, or weight loss. However, the trials had some methodological limitations including small sample sizes and short durations. In addition, no studies to date have assessed effects according to socioeconomic or ethnic group or measured the cost-effectiveness of such schemes. Monetary incentives are a promising strategy to modify dietary behavior, but more research is needed to address the gaps in evidence. In particular, larger, long-term RCTs are needed with population groups at high risk of nutrition-related diseases.

Impact of Targeted Financial Incentives on Personal Health Behavior

“…A nutrition study testing the effect of food provision to predominantly White, well-educated men and women recruited through newspaper advertisements, with and without a cash payment contingent on weight loss, found that differences among intervention groups were small, but favored groups with free food provision; however, this effect did not persist at 30 months. All treatment groups gained weight gradually after 6 months, with a convergence in mean weight loss toward the control group once formal treatment was withdrawn at 18 months (Glenny et al, 1997;Goodman & Anise 2006;NHS Centre for Reviews and Dissemination, 1997;Wall, Mhurchu, Blakely, Rodgers, & Wilton, 2006). A similar finding was reported where incentives included free food or cost sharing of food.…”

Cost-effectiveness of a behavioral weight loss intervention for low-income women: The Weight-Wise Program

“…The incentives constituted the second highest cost for the entire Weight-Wise intervention (26% of total). However, previous research suggests that incentives have a positive effect on weight loss (Wall et al, 2006) and could be an important component for weight loss success. The personnel costs associated with the group sessions ($5308) comprised 31% of total costs.…”

Paying people to lose weight: the effectiveness of financial incentives provided by health insurers for the prevention and management of overweight and obesity – a systematic review

“…Previous systematic reviews of the effectiveness of financial incentives to enhance weight loss have limited their scope to randomized controlled trials (RCTs) in the academic literature (6,13,23,24). Most reviews base their findings on less than 10 included studies, each of these studies with relatively small sample sizes (6,23,24). These reviews have found generally positive but mixed results with respect to weight loss.…”