Objectives: To determine the effectiveness of Peruvian purple corn (Zea mays) administration in serum lipids levels reduction (hypolipidemic effect) in non hypertensive diabetic patients with dyslipidemia; to compare hypolipidemic effect of Peruvian purple corn and simvastatin. Design: Clinical essay. Setting: Instituto de Investigaciones Clinicas, Facultad de Medicina, Universidad Nacional Mayor de San Marcos, Lima, Peru. Participants: Non hypertensive dyslipidemic diabetic patients. Interventions: Between January and October 2006 two groups of 15 non hypertensive dyslipidemic diabetic patients were randomly formed, patients with recent diagnosis, without previous treatment and without chronic complications; one group recieved simvastatin 40 mg/day and the other group Peruvian purple corn (dehydrated and micropulverized pills 1g/day) for 30 days. Patients had low fat diet with weekly nu...