The perception of health risks and risky health behaviors are closely associated. In this paper, we investigate the accuracy of health risk perceptions among obese individuals, aged 50–62 years. We compare subjective risk perceptions for various diseases elicited in the American Life Panel to individual's objective risks of the same diseases. We find that obese individuals significantly underestimate their 5-year risks of arthritis or rheumatism and hypertension, whereas they systematically overestimate their 5-year risks of a heart attack and a stroke. Obese individuals are thus aware of some but not all obesity-related health risks. For given diseases, we document substantial heterogeneities in the accuracy of expectations across individuals. Copyright © 2013 John Wiley & Sons, Ltd.