Smoking, overweight and physical inactivity are three lifestyle risk factors associated with increased risks of cancer, heart disease and other chronic diseases. Using data from the 1985 and 1991 General Social Surveys, this study examines the prevalence of these risk factors by respondents' education levels, and how the prevalence of these risk factors changed from 1985 to 1991. The prevalence of smoking, overweight and physical inactivity varied widely by respondent's education levels. In 1991, persons with more education had consistently lower rates for all three risk factors than those with lower educational levels. Smoking and sedentary living declined between 1985 and 1991, but the prevalence of overweight increased. However, except for physical activity, little progress was made in narrowing the socio-economic differences for these risks. Declines in the prevalence of health risks varied by educational level and by sex within educational level. This has implications for future patterns of chronic disease morbidity and mortality. Differences in risk factor prevalence between socioeconomic groups may be partly due to differences in how each group acquires and interprets health information, and to differences between groups' exposure to environments that support healthy lifestyles.