Coronary risk factors are described in 288 medically treated hypertensives, 1293 untreated hypertensives and 15,029 normotensives. Cholesterol in untreated men and women was 0.37 mmol/l and 0.35 mmol/l higher than in normotensives (p less than 0.001). Non-significant differences were observed between those untreated and treated. Treated men and women had 0.16 mmol/l and 0.14 mmol/l lower HDL cholesterol than untreated (p less than 0.01). Between untreated and normotensives non-significant differences were found. Triglycerides were 0.27 mmol/l and 0.22 mmol/l higher in treated than in untreated men and women (p less than 0.01). Normotensive men and women had 0.33 mmol/l and 0.10 mmol/l lower triglycerides than untreated (p less than 0.01). The results suggest that the increased cholesterol in hypertensives was present originally, while the decreased HDL cholesterol and elevated triglycerides probably were evoked by drugs. The importance of consideration of the whole constellation of risk factors in order to reduce the mortality from coronary heart disease by antihypertensive drug treatment is emphasized.