You've probably seen food labels touting oatmeal as a food that lowers your cholesterol. That's because oats contain soluble fiber. According to research, soluble fiber may help lower blood cholesterol levels (thereby reducing the risk of heart disease) when it is included in a diet that is ALSO low in saturated fat and cholesterol. Here's the catch: You need to eat a sizable quantity of oats to reap their benefits. You must eat approximately 1 1/2 cups of cooked oatmeal (about 3/4 cup raw) every day to get the amount of soluble fiber necessary to lower your cholesterol.