Great question. Vegetarians choose not to eat meat products where vegans choose not to eat any animal products like eggs, milk, and cheese. Being that a traditional alfredo sauce is made with heavy cream and Parmesan cheese, it would be a suitable dish for a vegetarian diet, but not for someone following a vegan diet. But my Vegan Alfredo Sauce Recipe sure does rival just about any traditional alfredo sauce, so I'm sure you could serve it to vegans and non-vegans alike and everyone would be happy.