title: Perceptions of Weight Status in Overweight and Obesity
Creators: name: Oldham, MF
Publisher: name: University of Liverpool Repository
Year: 2018

description: Individuals with overweight and obesity frequently underestimate their weight status and underestimation is more pronounced in areas with high rates of obesity. After a literature review in Chapter 1, Chapter 2 examines whether male overweight and obesity is visually underestimated and whether exposure to heavier bodies results in greater underestimation. In Study 1, 1000 participants estimated the weight status of men with normal weight, overweight and obesity in an online survey. The weight status of men with overweight and obesity was frequently underestimated. In Study 2, 90 participants reported how the size of their male peers compared to an overweight male and estimated the weight status of 10 men with overweight and obesity in a paper based survey. Those with heavier peers were more likely to underestimate overweight and obesity. Finally in Study 3, 230 participants completed a between-subjects, online study in which they were exposed to men with normal weight or obese BMI’s or control images before estimating the weight status of a male with overweight. Exposure to slimmer bodies reduced underestimation of overweight. Chapter 3 examines whether male and female overweight and obesity is visually underestimated and whether visual body size norms explain why exposure to heavier bodies increases underestimation of overweight. In Study 1, 91 participants estimated the weight status of men and women with normal weight, overweight or obesity in an online survey. Male and female overweight and obesity was frequently underestimated. In Study 2, 79 participants reported visual body size norms and estimated the weight status of men and women with overweight in an online survey. Those who perceived larger bodies as being normal were more likely to underestimate overweight. Finally in Study 3, 290 participants completed an online, between-subjects study in which they were exposed to men or women with healthy weight or obesity, reported visual body size norms and estimated the weight status of a man or woman with overweight. Those exposed to obesity reported larger body size norms and were more likely to underestimate overweight. Some research suggests underestimation of overweight could be a barrier to weight loss whilst other studies find that identifying as overweight is associated with weight gain over time. As such, Chapter 4 examines whether the psychosocial experience of feeling overweight affects eating behaviour. In Study 1, 120 women participated in a between-subjects study, they wore an obese body suit or control clothing in public or private settings before tasting and rating snack foods. Women who wore the body suit ate more than women who wore the control clothing, regardless of setting. In Study 2, 150 men and women wore an obese body suit or control clothing before tasting snack foods. Women who wore the obese body suit ate more than women who wore the control clothing. There was no effect of clothing on male consumption. We examined possible mediators of this effect but did not find supporting evidence. This thesis suggests that overweight is frequently visually underestimated due to increases in obesity increasing the range of bodies which are perceived as being normal. Furthermore, identifying as overweight may lead to increased snack food consumption, but it is not clear why this occurs. Future research should identify the mechanism explaining why feeling overweight can lead to increased consumption, as this would inform the inclusion of additional support in weight loss interventions.