Lettuce or Lactuca sativa is a vegetable grown for its leaves which are widely consumed in salads all over the world. It is widely appreciated for its numerous health benefits which include lowering cholesterol levels, preventing cancer, fighting insomnia, managing diabetes, aiding digestion, and fighting inflammation.
Botanical name: Lactuca sativa
Botanical family: Asteraceae
History has shown that lettuce was first cultivated by the Egyptians. They transformed it from an oil producing weed (its seed were used to produce oil) into a food plant grown for its succulent leaves. Later on, lettuce spread to the Greeks and Romans, from where it further spread into other parts of Europe.
Interestingly, lettuce has some history of use in medicine. Its seeds have been used as anodyne or painkillers, and also galactogogues in stimulating the production of more milk during lactation. In folk healing, its leaves have been used treat insomnia, dry coughs, anxiety, and rheumatic pain. Overall, folk healers have labelled lettuce as a great healing food. They attributed most of its therapeutic applications with its carminative, sedative, diuretic, emollient, hypoglycaemic, aphrodisiac, anodyne, and antimicrobial properties.
Types of lettuce
- Romaine – Has long, upright heads, and used mainly for sandwich and salads.
- Iceberg – Also called Crisphead. The most popular type in United States. Has more water than other types, with a reduced flavor.
- Butterhead – Also known as Boston or Bibb lettuce, or Round lettuce in the UK. Possess a tender texture and sweet flavor.
- Stem – Used mostly in Asian cooking. This variety is grown for its seedstalk, rather than its leaves.
- Oilseed – This variety is grown for its seeds, which are pressed to extract oil, used mainly for cooking. It has few leaves.
- Leaf – Also referred to as Looseleaf or Bunching lettuce. It is the most planted. It has loosely bunched leaves, which are used mainly for salads.
The following is the composition of a butterhead lettuce:
- It contains very large amount of water, about 95% of its total content. This makes it one of the foods that are richest in water.
- It contains very low amount of carbohydrates. This is the main reason why it supplies a very little amount of energy, just 13 kcal per 100 gram serving.
- It also contain very little amount of fats, about 0.2% of its total content.
- Proteins are present in lettuce in significant amounts, at about 1.35 g per 100 gram serving.
- It terms of minerals, iron and potassium stands out among others. Other minerals present in significant quantities are phosphorus, magnesium, calcium, manganese, zinc and copper.
- On the other hand, vitamins such as provitamin A, B group vitamins and vitamin C are present in lettuce in a quite rich amounts.
- It contains a substance known as lactucin, which is attributed to its sleep-inducing property.
- It also contains vegetable fiber in about 1.1% of its total content. This is quite a fair amount, considering the fact that most of its content is water. The fiber in this wonderful leaf vegetable gives it a mild laxative effect.
8 Medicinal uses of lettuce
- Relieves constipation
- Fights insomnia
- Manages diabetes
- Aids weight loss
- Protects nervous system
- Lowers cholesterol levels
- Prevents cancer
- Fights inflammation
Lettuce consumption may be found very helpful in cases of constipation, as it facilitates the removal of feces due to its fiber content and high water content. Fiber stimulates peristaltic action of the gut, which is important in passing stool down the colon. Besides, it adds some bulk to stool, an action which makes defecating easier and faster.
For those battling with insomnia or simply those who find it very difficult to sleep at night, then this is good news for you. Since folk healing age, lettuce has been known for its sleep-inducing property. This has been attributed to a compound found in it, known as lactucin, which has been scientifically proven to have analgesic and sedative properties.
When finding hard to sleep, especially at night, you can curb that by taking a few leaves of lettuce or its juice in moderated amounts.
The very low carbohydrate content of lettuce makes it easily tolerated by the diabetics. It has a glycemic index of just 15. If you are unaware, glycemic index is a relative ranking of carbohydrates in foods according to how they affect glucose levels in the blood. Foods with low glycemic index are those that have a value of 55 or less out of a maximum value of 100.
Having just 15 as glycemic index, makes lettuce a good food for the diabetics. Foods with low glycemic index are more slowly digested, absorbed and metabolized. Thus, they cause only a slow increase in blood sugar level.
Aids weight loss
After eating a lettuce, a great feeling of satiety is experienced. This makes you eat less amount of food in total, especially those high fat and calorie snacks most people consume in-between meals. Moreover, it provides a few amount of calories which makes it tolerable by the obese. It also contains high amount of water.
The reasons above justify why lettuce is so good for weight loss. If you are planning to shed off some weight, then don’t miss out on including lettuce as part of your weight loss plans.
Nervous system disorders
The regular consumption of lettuce produces a mild sedative effect. It also supplies necessary B group vitamins for nervous system wellness. It may be found very beneficial in cases of anxiety, stress, and nervousness.
A study published in the British Journal of Nutrition, found supplementation of a high-cholesterol high-fat diet with lettuce to improve plasma cholesterol and lipid levels, prevent lipid peroxidation and increase antioxidant defense system (1). This shows that lettuce consumption may reduce the risk factors for cardiovascular diseases.
Excess cholesterol in the body can clump in our arteries, and possibly block the flow of blood to vital organs such as the heart and brain, conditions that can lead to heart attack and stroke. So, lowering and maintaining proper cholesterol levels in the blood is essential to an improved cardiovascular health. And lettuce may help with that.
Recently, a research has shown the potential of lettuce to kill leukaemia and breast cancer cells (2). Also, lettuce is full of antioxidants such as vitamin C, vitamin K, vitamin A, and zinc. These antioxidants fight the formation of cancer cells by limiting the activities of free radicals in our body. These free radicals when at high concentration, can damage major components of the cell including DNA and its proteins. This damage, especially to DNA, plays a major role in the development of cancer.
Lettuce has some anti-inflammatory properties which has been associated with its content of polyphenols, especially quercetin (3). Due to this, lettuce may be found helpful in managing a number of inflammatory conditions such as allergies, infections, heart disease, and relieving pain associated with arthritis.