Lettuce

Lettuce (Lactuca sativa L.) is a major fresh vegetable and its leaves are commonly found in salad mixtures and sandwiches. In some eastern countries like China and Egypt, stems instead of leaves of lettuce are consumed, either cooked, raw, pickled, dried, or as a sauce. Some less common uses for lettuce include a cigarette without nicotine made from lettuce leaves, edible oil extracted from seeds of a primitive lettuce, and a sedative made of dried latex contained in stems and other tissues. Lactucarium, the dried latex produced from a wild lettuce relative, Lactuca virosa L., is used to make a sleep-inducing medicine (Ryder, 1986).