Impact of diagnostic labels and causal explanations for weight gain on diet intentions, cognitions and emotions: An experimental online study

Disease labels and causal explanations for certain symptoms or conditions have been found to have both positive and negative outcomes. For example, a diagnosis of polycystic ovary syndrome could conceivably motivate a person to engage in weight management, which is the recommended first line treatment. Furthermore, doctors may feel more comfortable discussing weight when linked to a medical condition. However, such a diagnosis may elicit feelings of increased anxiety, perceived severity and reduced sense of control. Mixed findings are also evident for impacts of genetic explanations on psychosocial outcomes and behaviours. Using hypothetical scenarios presented in an online survey, participants were asked to imagine that they were visiting their general practitioner due to experiencing weight gain, irregular periods, and more pimples than usual. Participants were randomised to receive different diagnostic labels ('polycystic ovary syndrome', 'weight' or no label/description) and causal explanations (genetic or environmental) for their symptoms. Primary outcomes assessed included intention to eat a healthier diet and perceived personal control of weight (average score on scale 1-7 across 3 items). Secondary outcomes included weight stigma, blameworthiness, worry, perceived severity, self-esteem, belief diet will reduce risks and menu item choice. Participants were 545 females aged 18-45 years (mean = 33 years), living in Australia, recruited through a national online recruitment panel. The sample was overweight on average (BMI = 26.5). Participants reporting a PCOS diagnosis were excluded from analyses. We found no main effects of the label or explanation on intention to eat healthier or perceived personal control of weight. For secondary outcomes, those given the genetic explanation reported higher weight stigma (range 1-7; MD = 0.27, 95%CI: 0.011,0.522), greater worry (range 1-7; MD = 0.27, 95%CI: 0.037,0.496), lower self-esteem (range 10-40; MD = 1.26, 95%CI: 0.28 to 2.24) and perceived their weight as more severe (range 1-7; MD = 0.28; 95% CI: 0.05,0.52) than those given the environmental explanation, averaged over disease label given. These findings further highlight the deleterious effects of genetic explanations on psychosocial outcomes and reinforce the need for caution when communicating the aetiology of weight-related health issues.