A hypotensive effect of active vitamin D treatment (alphacalcidol 1 mg daily) has previously been reported in three double-blind, placebo-controlled studies over 4-6 months in subjects with mild primary hyperparathyroidism (HPT), intermittent hypercalcemia and essential hypertension. The commonly used antihypertensive drugs, thiazides and betablockers, both induce impairments in both glucose and lipid metabolism and the thiazides are known to cause an elevation of serum urate. The effects of vitamin D treatment on these metabolic variables were recorded in these studies. Alphacalcidol did not induce any changes in fasting glucose HbA1c or insulin, serum triglycerides, cholesterol or serum urate in any of the treated groups. Neither was HDL cholesterol affected, except for a rise seen in the HPT subjects. It is therefore concluded that no major metabolic alterations in glucose or lipid metabolism or serum urate accompany the hypotensive effect of vitamin D.