Data on height, weight, illness, medical care consumption, and demographic variables for 19,126 Dutch adults aged 20 years or older were obtained from three annual Health Interview Surveys. Data on severely overweight (Body Mass Index 30.0-40.0 kg/m2) and moderately overweight (BMI 25.0-29.9 kg/m2) subjects were compared with those on non-overweight persons (BMI 20.0-24.9 kg/m2), taking into account effects of sex, age, and educational level. In men, severe overweight was associated with hypertension, especially in men under 50 years of age. In women, severe overweight was associated with hypertension, diabetes, varicose veins, asthma/bronchitis, and hemorrhoids. Increased utilization of medical care and medications were also associated with severe overweight. For moderately overweight subjects, these associations were less clear or absent.