The follow-up of arteriopathic subjects who have already been hospitalized (abdominal-peripheral vascular district 79% of patient and supra-aortic branch district 21%) has been carried out for around 10 years using an out-patient regime at the Institute of General and Cardiovascular Surgery of Milan. During outpatient visit the main risk factors for arteriosclerosis are routinely checked and treated if required; among the various therapies for metabolic control particular emphasis is placed on diet since its influence on the metabolism is well known, above all in the long term. The efficacy of this treatment has been evaluated by evaluating blood chemical changes (total cholesterol, LDL cholesterol, HDL cholesterol, triglycerides, VLDL and glycemia) in a group of patients who followed the diet in comparison to a group which did not. The results obtained show that in dieting patients there was a statistically significant decrease in blood values for total cholesterol, LDL cholesterol, triglycerides and VLDL, together with a decrement, which failed to reach statistical significance, in glycemia and HDL cholesterol. In non-dieting patients it was found that all parameters increased but that this was only statistically significant for total cholesterol and HDL cholesterol. The control of risk factors for arteriosclerosis through diet therapy therefore appears to be satisfactory even for secondary prevention in surgical arteriopathic subjects. It is important to underline that these results were not obtained under conditions of clinical research but in the reality of day-to-day clinical and therapeutic activity whose efficacy is vitally important for scientific health.