Assessment in humans of hypolipidemia induced by orotic acid.

The hypolipidemia induced by oral orotic acid in rats but not in other experimental species was investigated in human adults. Twelve outpatients in a medically-supervised weight reduction program participated in the study. After adaptation to their restricted dietary regime for at least 8 weeks, all subjects were given placebos (1 g lactose/day) for 2 weeks, then orotic acid (1 g/day) for 4 weeks, followed by placebos for 2 more weeks. Pertinent dietary, urinary, and serum parameters were monitored biweekly and intake of calories, carbohydrate, protein and fat was similar throughout. The ingestion of orotic acid did not lower serum triglycerides or cholesterol in these subjects. Since the daily dose tested corresponds to the orotic acid in 12 liters of cow's milk, milk orotic acid at levels normally consumed should not be considered a hypolipidemic or hypocholesteremic agent for humans.