Lettuce (Lactuca sativa) is native to central Asia, and a member of the Asteraceae (Daisy) Family, making it a relative of sunflowers and artichokes. The genus name Lactuca is from the Latin lac, meaning, "milk" based on the milky white juice that sometimes exudes from lettuce plants. The species name sativa means "with a long history of cultivation." Augustus Caesar once erected a monument to lettuce, believing that this plant healed him.
Lettuce is alkaline, cool, bitter and sweet. It helps dry dampness in the body, including phlegm and yeast overgrowth. It is also anodyne (pain relieving), anti-inflammatory, antioxidant, antispasmodic, diuretic, expectorant, galactagogue (increases mother's milk) and sedative. Lettuce has a slowing effect upon digestion.
Lettuce has been used to treat acid indigestion, anemia, arthritis, catarrh, colitis, constipation, cough, gastritis, gout, insomnia, irritable bowel, obesity, sexual addiction, stress, and ulcers. Lettuce is considered beneficial in helping to prevent stomach and endometrial cancers, cataracts, stroke and heart disease. Topically, lettuce has been used as a poultice for swollen joints and bruises. Lettuce contains chlorophyll, lactucin (a calming alkaloid), beta-carotene, folic acid, vitamins B1, B6, C, E, K, and the minerals, calcium, iron, potassium, and silicon. It can be 92-95% water.
Though three quarters of US salad sales are iceberg lettuce, it is the least nutritious, though survives shipping the best. Darker lettuce, like Bibb, Boson and Romaine (from Rome) are more nutritious than light colored ones. Romaine gets most of its leaves exposed to sunlight, which boosts its nutritional content. Common uses of lettuce include salad, sandwiches, hors d'oeuvres, and to make "wraps" stuffed with fillings.
Look for fresh, crisp greens without signs of decay. It is a highly sprayed plant, so buy organic. Lettuce keeps best in its own sealed container. Storing it with apples, pears and tomatoes emit an ethylene gas will cause lettuce to turn brown more quickly. A salad spinner is a great kitchen addition to dry the leaves before applying dressing. Leaves should be torn, rather than cut, to prevent oxidation and browning.