Communicating evidence about the environment’s role in obesity and support for government policies to tackle obesity: a systematic review with meta-analysis

Abstract

Public support for many policies that tackle obesity by changing environments is low. This may reflect commonly held causal beliefs about obesity, namely that it is due to failures of self-control rather than environmental influences. Several studies have sought to increase public support by changing these and similar causal beliefs, with mixed results. The current review is the first systematic synthesis of these studies. Searches of PsycInfo, Medline, Web of Science, Scopus, and Open Grey yielded 20 eligible studies (N = 8977) from 11,776 abstracts. Eligible studies were controlled experiments with an intervention group that communicated information about the environment's role in obesity, and a measure of support for environment-based obesity policies. The protocol was prospectively registered on PROSPERO. Metaanalyses showed no evidence that communicating information about the environment's influence on obesity changed policy support or the belief that the environment influences obesity. A likely explanation for this null effect is the ineffectiveness of interventions that were designed to change the belief that the environment influences obesity. The possibility remains, however, that the association observed between beliefs about the causes of obesity and attitudes towards obesity policies is correlational and not causal.

Monitoring changes in community support for policies on obesity prevention

“…39,40 Reynolds et al (2020) has recently challenged these results, finding no change in support for policies when the environmental causes of obesity were communicated, 41 concluding in a metaanalysis that the different results could be due to insufficiently persuasive messages. 42 The 'nanny state' narrative by the food industry or in media may also be another contributor to how the public perceives regulatory measures. Although causation cannot be established, there is evidence that support for evidence-based alcohol policy in New South Wales decreased compared with many other Australian states following negative public discourse about government restrictions on alcohol availability in New South Wales.…”

Public support for obesity prevention policies in Western Australia from 2012 to 2020: Findings from cross‐sectional surveys

“…45 However, these studies have typically presented messages delivered either once or repeatedly over very short periods of time through singular mediums such as written passages, text messages or infographics, which may limit their potential impact on beliefs and attitudes about obesity and its causes, as well as the role and effectiveness of a range of policy options to improve healthy eating. 45 Recent Australian research indicates that exposure to carefully crafted video counter-advertisements exposing the intent and detrimental impact of industry marketing of harmful products (in this case alcohol) can bolster public support for policy to restrict such marketing. 46 Research has demonstrated that repeated waves of messaging delivered to populations through multiple mediums, such as a combination of TV, radio, print media, online and outdoor media, over long periods of time are effective at changing beliefs, attitudes and knowledge.…”

“…Experimental studies testing the effect of messages to increase awareness of the environmental causes of obesity and support for obesity prevention policies have found, perhaps counter‐intuitively, that both beliefs and policy support are somewhat resistant to change even when presented with supporting evidence 45 . However, these studies have typically presented messages delivered either once or repeatedly over very short periods of time through singular mediums such as written passages, text messages or infographics, which may limit their potential impact on beliefs and attitudes about obesity and its causes, as well as the role and effectiveness of a range of policy options to improve healthy eating 45 . Recent Australian research indicates that exposure to carefully crafted video counter‐advertisements exposing the intent and detrimental impact of industry marketing of harmful products (in this case alcohol) can bolster public support for policy to restrict such marketing 46 …”