There's a common myth that fresh fruits and vegetables are higher in vitamins and minerals than canned or frozen. Not so! Take the case of tomatoes. Canned tomatoes are actually a better source of lycopene than fresh tomatoes. Lycopene is a carotenoid pigment (red color) that may aid in preventing heart diseases and certain cancers, such as prostate and ovarian cancer. Tomato paste is actually six times higher in lycopene than fresh tomatoes. Canned vegetables tend to be higher in sodium than fresh or frozen, so look for vegetables packed as "no added salt". Rinsing them prior to use also reduces the sodium content by 50%.