Despite the strong link between obesity and cancer development, individuals are less likely to identify obesity as a risk factor for cancer than family history. Family history of cancer has been documented to influence perceived risk of developing cancer, yet it is unclear if excess weight impacts cancer risk perceptions. The purpose of this study was to examine absolute and relative risk perceptions for cancer by weight status. Cross-sectional data were obtained from the National Cancer Institute's 2011 Health Information National Trends Survey (n = 2585). Demographics, anthropometric data, family history of cancer, health behaviors, and absolute and relative cancer risk perceptions were evaluated. The effect of weight and family history on absolute and relative cancer risk perceptions was analyzed through weighted descriptive and logistic regression analyses. 22.8 and 28.6 % of subjects reported that they were very unlikely/unlikely to develop cancer in their lifetime (absolute risk) and when compared to others their age (relative risk), respectively. Findings indicated differences in risk perceptions between those with and without a family history of cancer (p < 0.0001). No significant differences were found between BMI categories for absolute cancer risk perceptions despite stratification by family history. Obese subjects were more likely to have an increased relative risk perception of cancer compared to healthy weight subjects (p = 0.0066); this association remained significant when stratified by family history (p = 0.0161). Educating individuals, especially those who are overweight/obese, about the impact of excess weight on cancer risk may improve risk accuracy and promote cancer risk reduction through weight management.
Keywords: Cancer; Obesity; Risk perception.