The Trial of Antihypertensives Interventions and Management (TAIM) was a multicenter double-blind placebo-controlled clinical trial of drug and diet combinations for the treatment of mild hypertension among 878 participants, ages 21 to 65, 110% to 160% ideal weight, and with baseline diastolic blood pressure 90 to 100 mm Hg. The drugs used were placebo, chlorthalidone (25 mg/daily) or atenolol (50 mg/daily). The diets studied were usual, weight loss, sodium reduction/potassium increase. Trial end points were 6-month diastolic blood pressure change, cardiovascular risk change, and quality of life change. Either drug combined with weight loss produced the greatest blood pressure reduction of 15 mm Hg, compared to 8 mm Hg on placebo/usual diet. Adding sodium restriction to either drug did not enhance blood pressure lowering effect. Drugs outperformed diet in terms of antihypertensive effect. However, those on placebo and assigned to weight reduction who lost more than 4.5 kg and those on sodium restriction who reduced sodium to less than 70 mEq daily lowered blood pressure to a similar extent as those on either of the two drugs alone. Cardiovascular risk at 6 months relative to baseline ranged from 0.85 in weight loss/atenolol subgroup to 1.04 in the usual diet/chlorthalidone subgroup. Blacks were more responsive to chlorthalidone plus weight loss and whites to atenolol plus weight loss. Quality of life, as measured by scales of distress and well-being, was favorably affected by weight reduction. Although there were few side effects of the drugs and most patients improved on most parameters, sexual complaints were worsened among those on chlorthalidone and usual diet compared to placebo.(ABSTRACT TRUNCATED AT 250 WORDS)