A systematic review of implicit attitudes and their neural correlates in eating behaviour

An increasing number of studies suggest that implicit attitudes towards food and body shape predict eating behaviour and characterize patients with eating disorders (EDs). However, literature has not been previously analysed; thus, differences between patients with EDs and healthy controls and the level of automaticity of the processes involved in implicit attitudes are still matters of debate. The present systematic review aimed to synthesize current evidence from papers investigating implicit attitudes towards food and body in healthy and ED populations. PubMed, EMBASE (Ovid), PsycINFO, Web of Science and Scopus were systematically screened and 183 studies using different indirect paradigms were included in the qualitative analysis. The majority of studies reported negative attitudes towards overweight/obese body images in healthy and ED samples and weight bias as a diffuse stereotypical evaluation. Implicit food attitudes are consistently reported as valid predictors of eating behaviour. Few studies on the neurobiological correlates showed neurostimulation effects on implicit attitudes, but how the brain automatically processes implicit evaluations remains an open area of research. In conclusion, implicit attitudes are relevant measures of eating behaviour in healthy and clinical settings, although evidence about their neural correlates is limited.