Lettuce (Lactuca sativa) is an annual plant of the aster or sunflower family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce was first cultivated by the ancient Egyptians who turned it from a weed, whose seeds were used to produce oil, into a plant grown for its leaves. Lettuce spread to the Greeks and Romans, the latter of whom gave it the name "lactuca", from which the English "lettuce" is ultimately derived. By 50 AD, multiple types were described, and lettuce appeared often in medieval writings, including several herbals. The 16th through 18th centuries saw the development of many varieties in Europe, and by the mid-18th century cultivars were described that can still be found in gardens. Europe and North America originally dominated the market for lettuce, but by the late 1900s the consumption of lettuce had spread throughout the world.

Generally grown as a hardy annual, lettuce is easily cultivated, although it requires relatively low temperatures to prevent it from flowering quickly. It can be plagued with numerous nutrient deficiencies, as well as insect and mammal pests and fungal and bacterial diseases. L. sativa crosses easily within the species and with some other species within the Lactuca genus; although this trait can be a problem to home gardeners who attempt to save seeds, biologists have used it to broaden the gene pool of cultivated lettuce varieties. World production of lettuce and chicory for calendar year 2010 stood at 23,620,000 metric tons (23,250,000 long tons; 26,040,000 short tons), over half of which came from China.

Lettuce is most often used for salads, although it is also seen in other kinds of food, such as soups, sandwiches and wraps. One type is grown for its stems, which are eaten either raw or cooked. Lettuce is a good source of vitamin A and potassium, as well as a minor source for several other vitamins and nutrients. Despite its beneficial properties, lettuce when contaminated is often a source of bacterial, viral and parasitic outbreaks in humans, including E. coli and Salmonella. In addition to its main use as a leafy green, it has also gathered religious and medicinal significance over centuries of human consumption.

Read more about Lettuce:  Taxonomy and Etymology, Description, History, Cultivation, Production, Culinary Use, Nutrition and Health

Other articles related to "lettuce":

Lettuce Sandwich - Health Benefits
... A lettuce sandwich is a sleep-inducing remedy for insomnia ... This is due to opiate-like chemicals contained in lettuce that help relax and sedate the body, along with the sleep-inducing effect of the carbohydrates in the bread ... Lettuce sandwiches (no bread) are also eaten to promote weight loss ...
List Of Tokyo Mew Mew Characters - Mew Mews - Lettuce Midorikawa
... Lettuce Midorikawa (碧川 れたす, Midorikawa Retasu?) is the third member of the Mew Mews formally introduced to the readers ... Infused with the DNA of a Finless Porpoise, Lettuce's legs can change into a porpoise's tail while she is underwater, greatly improving her swimming ability ... In the anime adaptation, this change can only occur when Lettuce is in the presence of mew aqua ...
Lettuce Sandwich - Metaphors
... The lettuce sandwich has also become a cultural metaphor to represent something unattractive, unappealing, weak, or mundane ... In this sense, the term "limp (or soggy) lettuce sandwich" is often used ... Being on a "lettuce sandwich diet" refers to getting by on the bare minimum with absolutely nothing more than the necessities of life ...
Lettuce - Nutrition and Health - Religious and Medicinal Lore
... usual purpose as an edible leafy vegetable, lettuce has had a number of uses in ancient (and even some more modern) times as a medicinal herb and ... For example, ancient Egyptians thought lettuce to be a symbol of sexual prowess and a promoter of love and childbearing in women ... Lettuce has mild narcotic properties – it was called "sleepwort" by the Anglo-Saxons because of this attribute – although the cultivated L ...
Lettuce Sandwich
... A lettuce sandwich is either a bread sandwich made with lettuce as its only filling, or a breadless sandwich, with a filling optionally inserted between two ... In the later case it is often referred to as a lettuce wrap ... should not be confused with other sandwiches that use lettuce as one of many ingredients, such as the BLT sandwich or the tomato and lettuce sandwich ...

Famous quotes containing the word lettuce:

    I did toy with the idea of doing a cook-book.... The recipes were to be the routine ones: how to make dry toast, instant coffee, hearts of lettuce and brownies. But as an added attraction, at no extra charge, my idea was to put a fried egg on the cover. I think a lot of people who hate literature but love fried eggs would buy it if the price was right.
    Groucho Marx (1895–1977)