OBJECTIVE: To evaluate the contributions of socioeconomic, lifestyle, and body weight factors to predicted risk of coronary heart disease (CHD) in the population and thus provide a focus for policies on prevention. DESIGN: Prospective study and cross-sectional population health survey. SUBJECTS: In all, 3090 men in the Framingham study and 2571 men in the 1998 Health Survey for England (HSE) aged 35-74 y with no history of cardiovascular disease participated in the study. MEASUREMENTS: Data on sex, age, systolic blood pressure and antihypertensive medication, total and high-density lipoprotein cholesterol levels, diabetes, and their association with the incidence of myocardial infarction and fatal CHD in the Framingham study population were used to derive functions for predicting individual 10-y risk of CHD. These functions were applied to the same data on participants in the HSE. High risk was defined as 10-y CHD risk > or = 15%. The proportion of high risk in the English population attributable to each of the risk factors examined was assessed. RESULTS: In all, 32% of men in England had predicted 10-y CHD risk > or =15%. Such high risk was significantly associated with body mass index (BMI, kg/m2), waist:hip ratio (WHR), smoking, and levels of physical activity, educational attainment, and income (all P < or = 0.007). In this population, 47% of high CHD risk was attributable to excess body weight--BMI > or = 25 kg/m2 and/or WHR > or = 0.95--and 31% to the sum of the four other significant factors: lack of educational qualifications, low income, smoking, and physical inactivity. CONCLUSION: Overweight and obesity now dominate the standard risk factors of CHD in men and should be the focus of national policies for prevention.