Tuna is a mild-flavored fish that is an excellent addition to your diet. Tuna can be found raw, canned, steamed and frozen at most grocery stores. Raw tuna, depending on the cut, can be either high or low in fat content, with the highest fat content being found in the light-colored portion of the fish. A large portion of this fat value is in the form of omega-3 fatty acids which are suggested to reduce your risk of cancer and heart disease. Most canned tuna has a very low fat content as most of the oils have been withdrawn during the canning process. Tuna is known to be an excellent source of high quality protein, Omega-3, as well as important nutrients including magnesium, potassium and B vitamins. Many people choose to can fresh tuna in order to enjoy a premium grade tuna without the premium price of store-bought canned fish oil benefits. Catch your own tuna or purchase fresh tuna from the store and can it yourself to improve the taste of your tuna salad, casseroles or any number of your favorite tuna recipes.