Beef and most types of fish are usually higher in potassium than chicken, turkey, and tuna. For example, a 3-ounce ground turkey patty has 288 mg of potassium, a 3-ounce serving of canned tuna has 283 mg, a 3-ounce serving of salmon has 387 mg, and a 3-ounce steak has about 360 mg. Your doctor or dietitian can help you decide which to eat and how to watch your portions.