Blood pressure, pulse and body mass index were measured in 64 healthy black men, aged 20-44 years, from an urban region in Zaire. A required blood test for AIDS was extended to include plasma renin activity (PRA), total cholesterol (TC), triglycerides (TG) and high density lipoprotein cholesterol (HDL-C). Mean BMI was 21.99. Mean BP was 132.2/85.3 mmHg and hypertension (> 160/95 mmHg) was found in 17.2% of subjects. Very low PRA was found in 28 subjects and high PRA in one normotensive man. Mean PRA was 1.3 +/- 1.2. Mean plasma TC, TG and HDL-C were 136, 84, and 46 mg/dl, respectively, and mean TC/HDL-C ratio was 3:1. The frequency of hypertension in this study population is higher than that previously described for a different segment of the same population. It is, however, offset by a more favourable lipid profile that determines a more favourable overall cardiovascular risk profile.