The tomato is the edible berry of the plant Solanum lycopersicum, commonly known as the tomato plant. The species originated in western South America and Central America. The Mexican Nahuatl word tomatl gave rise to the Spanish word tomate, from which the English word tomato derived. Plus, tomatoes are very low in calories; an average-sized tomato is just 22 calories and a large one is 33 calories. Carbs. Carbs comprise 4% of raw tomatoes, which amounts to fewer than 5 grams of carbs for a medium specimen (123 grams). Simple sugars, such as glucose and fructose, make up almost 70% of the carb content. Tomatoes are fruits that are considered vegetables by nutritionists. Botanically, a fruit is a ripened flower ovary and contains seeds. Tomatoes, plums, zucchinis, and melons are all edible fruits, but things like maple â??helicoptersâ?? and floating dandelion puffs are fruits too. Tomatoes are botanically defined as fruits because they form from a flower and contain seeds. Still, they're most often utilized like a vegetable in cooking. In fact, the US Supreme Court ruled in 1893 that the tomato should be classified as a vegetable on the basis of its culinary applications. Although in culinary terms, tomato is regarded as a vegetable, its fruit is classified botanically as a berry. As a true fruit, it develops from the ovary of the plant after fertilization, its flesh comprising the pericarp walls. tomato, (Solanum lycopersicum), flowering plant of the nightshade family (Solanaceae), cultivated extensively for its edible fruits. Labelled as a vegetable for nutritional purposes, tomatoes are a good source of vitamin C and the phytochemical lycopene. Tomatoes are the major dietary source of the antioxidant lycopene, which has been linked to many health benefits, including reduced risk of heart disease and cancer. They are also a great source of vitamin C, potassium, folate, and vitamin K. It contains many nutrients, including an antioxidant called lycopene. The lycopene in tomato is thought to play a role in preventing cancer. It's easier for the body to use lycopene that comes from tomato products, such as tomato paste or tomato juice, than from fresh tomatoes. The tomato was eaten by the Aztecs as early as 700 AD and called the â??tomatl,â?? (its name in Nahuatl), and wasn't grown in Britain until the 1590s.