objective: to determine whether the average drop in total cholesterol and ldl-cholesterol is higher in adult patients diagnosed with hypercholesterolemia who receive an hypocholesterolemic diet combined with a probiotic compared with those who receive only diet. materials and methods: a randomized controlled clinical trial. the sample consisted of 46 patients of both sexes who attended the pi？ero hospital outpatient center with a diagnosis of hypercholesterolemia from august 2009 to april 2011. they were assigned to two groups: one received an hypocholesterolemic diet and another the same diet plus a dairy product containing probiotic lactobacillus casei strain shirota. results: no significant differences were found in the average drop in total cholesterol between the group that followed the hypocholesterolemic diet and the one that followed the same diet combined with the probiotic (p = 0.386), whereas a significant difference (p <0.001) was observed between the initial and final total cholesterol in both. in the case of ldlcholesterol, no significant differences were found in its average drop between both groups (p = 0.313) as well, but there was a significant difference (p <0.001) between the initial and final ldl . conclusions: in this study no significant differences were found in the average drop in total cholesterol and ldl-cholesterol between the group that followed only the hypocholesterolemic diet and the group that followed the diet with the probiotic. however, the results obtained confirm that the adoption of a meal plan designed to achieve a reduction in total cholesterol and ldl-cholesterol is effective, becoming a mainstay for the prevention and treatment of cardiovascular diseases.