Most people know that processed foods are often loaded with sodium. But you may be surprised to learn that some packages of uncooked “100 percent natural” skinless boneless chicken breasts contain a fair amount of sodium too. Processors often inject poultry with up to a 15-percent solution of saltwater or chicken broth to “enhance flavor and tenderness.” A 4-ounce portion can contain 180 to 320 milligrams of sodium compared to 40-75 milligrams of sodium in the same size "unenhanced" portion. Look for the sodium content on the Nutrition Facts panel if you’re watching your sodium or salt intake.
Source: U.S. Department of Agriculture