Lettuce leaves are one of the very low calorie green-vegetables. 100 g fresh greens provide just 15 calories.Nonetheless, they are the store house of many phyto-nutrients that possess health promoting and disease prevention properties.
Vitamins in lettuce are plentiful. Its fresh leaves are an excellent source of several Vitamin A and beta carotenes. Just 100 g of fresh, raw-lettuce provides 247% of daily vitamin A, and 4443 µg of beta-carotene(Carotenes convert into vitamin A in the body; 2 µg of carotene is considered equivalent to 1 IU of vitamin A). These compounds have antioxidant properties. Vitamin A is required for maintaining healthy mucus membranes and skin, and is also essential for vision. Consumption of natural fruits and vegetables rich in flavonoids helps to protect the body from lung and oral cavity cancers.
It is a rich source of vitamin K. Vitamin K has a potential role in the bone metabolism where it thought to increase bone mass by promoting osteotrophic activity inside the bone cells. It also has established role inAlzheimer's disease patients by limiting neuronal damage in the brain.
Fresh leaves contain good amounts folates and vitamin C. Folates are part of co-factors in the enzyme metabolism required for DNA synthesis and therefore, play a vital role in prevention of the neural tube defects in the baby (fetus) during pregnancy.