It is easily cultivated, although it requires relatively low temperatures to prevent it from flowering quickly. There are about six varieties of cultivars exist based upon their head formation and leaf structure.
Depending on the variety, this plant is an excellent source of vitamin K and vitamin A, with higher concentrations of the provitamin A compound, beta-carotene, found in darker green lettuces, such as Romaine.
With the exception of the iceberg variety, lettuce is also a good source of folate and iron.
In addition to its usual purpose as an edible leafy vegetable, it has had a number of uses in ancient (and even some more modern) times as a medicinal herb.
Some of the health benefits of lettuce that have been confirmed by modern scientific research include:
1. Lowers Cholesterol Levels
A study was conducted on mice to test the impact of lettuce consumption on fat and cholesterol. The results indicated a significant reduction of cholesterol levels compared to mice that weren’t fed lettuce.
2. Antioxidant Properties
Studies have shown that lettuce possesses antioxidants which are very necessary for human health. Antioxidants act as barriers to free radicals, which are produced during cellular metabolism.
These free radicals attack healthy tissues, cells and the DNA inside them. They can often cause healthy cells to mutate into cancer cells.
3. Helps Weight Loss
Lettuce contains fiber and cellulose. Besides filling you up, fiber improves your digestion.
Improving your digestion may not sound like a good thing for losing weight, but it is actually essential for long term weight control.
4. Low Glycemic Index
Lettuce has an average glycemic index of 15, but because it has so few calories, its glycemic load is considered zero.
Foods with low glycemic indexes are great for anyone watching their blood sugars for medical reasons, or for weight management.
5. Protects Skin
The combination of vitamin E and vitamin C in this vegetable helps in keeping your skin healthy as you age.
Vitamin E also provides protection against the sun’s harmful ultraviolet rays and reduces the risk of cataracts and macular degeneration.
6. Proteins
Proteins are the building blocks of a developing body. They are needed for muscle development and many important metabolic reactions in the body. Lettuce contains a good 20 per cent of proteins in its total quantity.
7. Hair Benefits
Just like the rest of the body, your hair also needs adequate supply of nutrients, vitamins and minerals for their growth and health. Being highly nutritious, lettuce offers a range of benefits for your hair.
8. Anti-Cancer Properties
Lettuce leaf extracts can control certain type of cancer. Research on human cancer cells, particularly leukemia cells and breast cancer cells, were controlled to a significant extent after being treated with lettuce extracts.
The experiments also suggested that the weight ratio of human lettuce consumption required to kill 50% of leukemia cells would be 3 kg.
