common digestive system cancers, including stomach, mouth, and pharynx. Choose healthy fats Eating a diet high in fat increases your risk for many types of cancer. But healthy types of fat may actually protect against cancer. Avoid trans fat or partially hydrogenated oil found in packaged and fried foods such as cookies, crackers, cakes, muffins, pie crusts, pizza dough, French fries, fried chicken, and hard taco shells. Limit saturated fat from red meat and dairy to no more than 10% of your daily calories. Add more unsaturated fats from fish, olive oil, nuts, and avocados.