Background: Carotid intima media thickness (CIMT) is a marker of cardiovascular damage that can be modified by traditional risk factors. Aim: To determine attributable risk factors for a high CIMT among healthy adults. Material ana Methods: A sample of 1270 individuáis (636 males and 634 femóles) aged 44 ±11 years, was studied. Blood pressure, weight, height, lipidprofile and blood glucose were measured in all. CIMT and thepresence of atheroscleroticplaques were determined by carotid ultrasound. Standard criteria were used to define hypertension, dyslipidemia and diabetes. Results: Mean CIMT in the sample studied was 0.62 ± 0.01 mm and percentile 75 was 0.67. The most important risk factor for a CIMT over percentile 75 and thepresence of atherosclerotic plaques was hypertension with attributable risks of 54 and 57%, respectively. Conclusions: In this sample, the main risk factor for a high CIMT was hypertension.