Relationship of cash transfers with risk of overweight and obesity in children and adults: a systematic review

BACKGROUND: Cash transfer (CT) programs are an important type of social protection meant to reduce poverty. Whether CT programs increase the risk of overweight and obesity is unclear. The objective was to characterize the relationship between CT programs and the risk of overweight and obesity in children and adults. METHODS: We searched articles in PubMed, Embase, Cochrane, EconLit, Global Health, CINAHL Plus, IBSS, Health & Medical Collection, Scopus, Web of Science, and WHO Global Index Medicus in August 2021. Studies involving CT as the intervention, a control group, body mass index, overweight, or obesity as an outcome, and sample size > 300 were included. The Newcastle–Ottawa Scale was used for quality assessment. RESULTS: Of 2355 articles identified, 20 met the inclusion criteria. Because of marked heterogeneity in methodology, a narrative synthesis was used to present results. Thirteen of the studies reported that CT programs were associated with a significantly lower risk of overweight and obesity, eight studies showed no significant association, and one study reported a significantly increased risk of obesity in women. Quality assessment showed that most studies lacked sample size and power calculations, validation of exposure, descriptions of non-respondents or those lost to follow-up, and blinded outcome assessment. CONCLUSIONS: Overall, the studies were suggestive that CT programs either have no impact or decrease the risk of overweight and/or obesity in children, adolescents, and adults, but no firm conclusions can be drawn from the available evidence. This review demonstrated limitations in the available studies of CT programs and overweight/obesity. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12889-022-13533-x.