The green parts of the tomato plant are high in solanine, a toxic substance that is not eliminated by cooking, and this makes them poisonous to humans. The fruit also contains a limited amount of solanine, but it decreases as the fruit ripens and the little that remains has no adverse affect.
The tomato, or Solanum Lycopersicum, is a creeping plant in the Solanaceae family, originally from the Americas but deeply and successfully embedded in Italian cuisine since the 16th century, even becoming a symbol of Italian food.
There are numerous varieties of tomato, classified according to their shape and colour, which varies from green to intense red. The original wild form of this plant appears to have been Lycopersicum cerasiforme, or cherry tomato.