Currently, tomatoes are one of the most popular vegetables eaten by Americans. Tomatoes are members of the fruit family, but they are served and prepared as a vegetable. This is why most people consider them a vegetable and not a fruit. They are high in vitamin C and also provide beta-carotene. The National Cancer Institute published a study that showed an association between consuming a diet rich in tomato-based foods and a decreased risk of prostate cancer. Tomatoes contain large amounts of an antioxidant called lycopene, which may be responsible for this possible positive effect. Tomato paste and sauces contain a greater amount of lycopene, because they are more concentrated than fresh tomatoes. Lycopene is a bright red carotenoid pigment (phytochemical) found in tomatoes and other red fruits. Lycopene is the most common carotenoid in the human body and is one of the most potent carotenoid antioxidants. Its name is derived from the tomato's species classification, Solanum lycopersicum. Ironically, the highest natural concentrations of lycopene in food are found not in tomatoes, but in watermelon. Almost all dietary lycopene comes from tomato products, however. Recent research has indicated that lycopene, a carotenoid with potent antioxidant effects which is found in raw tomatoes, may be responsible for the protection against cancers. This is possibly the reason why people living in the Mediterranean who eat lots of tomatoes have a lower rate of some cancers.