Replace saturated fats, such as those found in beef and butter, with unsaturated oils from avocados, nuts, olives and seafood to lower your cholesterol and stave off heart disease, advises the USDHHS. These foods provide essential fats that help your body absorb the fat-soluble vitamins A, D E and K. They also contain dietary fiber, which promotes healthy levels of fat and sugar in your blood to prevent heart disease and diabetes.