Nutritional Value and Health Benefits of Lettuce
The nutritional value of lettuce varies with the variety. Lettuce in general provides small amounts of dietary fiber, some carbohydrates, a little protein and a trace of fat. Its most important nutrients are vitamin A and potassium. The vitamin A comes from beta carotene, whose yellow-orange is hidden by green chlorophyll pigments. Beta carotene, of course, is converted to vitamin A in the human body. The darker green, the more beta carotene.
According to the American Cancer Institute and the American Cancer Society, foods rich in vitamin A and C (antioxidants) offer protection against some forms of cancer. Along with other phytochemical, antioxidants reduce the risk of cancer of the respiratory system and intestinal tract.
Lettuce, except iceberg, is also a moderately good source of vitamin C, calcium, iron and copper. The spine and ribs provide dietary fiber, while vitamins and minerals are concentrated in the delicate leaf portion.
One cup raw leaf lettuce, chopped
- Calories 9
- Dietary Fiber 1.3
- Protein 1 gram
- Carbohydrates 1.34 grams
- Vitamin A 1456 IU
- Vitamin C 13.44
- Calcium 20.16
- Iron 0.62
- Potassium 162.4 mg
Preparation and Serving
Rinse lettuce just before serving in very cold water. Pat dry with a clean towel. Limp leaves can be revived by immersing in ice water for a few minutes. Tear lettuce leaves into pieces. If practical, do not cut or sliced lettuce leaves in advance. Damaged cut lettuce leaves release an ascorbic acid oxidase, which destroys vitamin C. Cut edges also discolor quickly.
Dry leaves before serving. Salad dressing will cling to dry lettuce leaves instead of sinking to the bottom of the salad bowl. Toss with your favorite dressing just before serving (or serve dressing on the side) Lettuce leaves covered with dressing will quickly wilt.
Due to the extremely high water content, 94.9%, there are no successful method of long-term home preservation for lettuce. Lettuce does not respond well to freezing, canning or drying. For optimal nutritional value, lettuce should be eaten while it is fresh and crisp.
The mild flavor of fresh lettuce leaves are well complimented by fresh or dry herbs. The base of most green salads is lettuce. Two or three lettuce varieties are good for both taste and texture. Mix leaf lettuce (Black-seed Simpson or Oak Leaf) with crisp lettuce (romaine or other crisphead) and accent with fresh herb leaves. The simplest way to appreciate a tossed green salad is with a vinaigrette dressing. Keep it simple. When the dressing becomes too complicated, the mild garden greens can be overpowered.