A member of the plant family Brassica oleracea, which also includes kale, cauliflower and broccoli, collard greens are also descendants of the wild cabbage, a plant that has its origins in Asia Minor, and was consumed as food since prehistoric times. Being a staple vegetable of the Southern United States, collard greens have a distinct mild, smoky flavor, and are prepared in a variety of ways. They have a unique appearance, with dark blue-green leaves that are smooth in texture and comparatively broader than the frilly-edged leaves of kale.
Nutritional Facts About Collard Greens
Collard greens are rich in vitamin A, vitamin C, manganese, folates, dietary fibers, and calcium. Also, these vegetables are an excellent source of potassium, vitamin B2 and vitamin B6, vitamin E, magnesium, protein, vitamin B1, vitamin B5, zinc, phosphorus, and iron. Hence, they are loaded with vitamins and minerals that are essential for our body. The tables given below show the various nutrients present in collard greens, along with the quantity of each present in 100 g of the vegetable.
Unlike other vegetables, collard greens offer more nutritional benefits when cooked than raw, as cooking breaks down the cell walls and releases higher levels of vitamins and minerals. But what about the calories in them? Well, being low in calories, fat and sodium content, these vegetables are considered a dieter's delight! In fact, one cup of freshly cooked collard greens contains 49 calories, while raw collard greens contain 11 calories.
From the tables of nutritional data that we have seen above, we can conclude that there are four major contributors to the nutritive value of collard greens, and these are as follows:
Collard greens have very high amounts of dietary fibers, both soluble and insoluble.
- Dietary fibers help control the levels of LDL cholesterol (bad cholesterol) in the blood.
- Among all leafy vegetables, collards have the greatest ability to lower blood cholesterol levels.
- This amazing ability of collards is due to its bile acid binding property, which makes way for the excretion of bile acids from the body. The excretion of bile acids stimulates the secretion of more of it, and since bile acids are synthesized from cholesterol, this ultimately results in lowering of cholesterol levels in the blood.
Collard greens are rich in substances known as phyto-nutrients, which have an array of health benefits. Phyto-nutrients are nothing but nutrients derived from plants that promote good health. Some of these present in collards are glucosinolates, caffeic acid, ferulic acid, quercetin, di-indolyl-methane, sulforaphane, lutein, lipoic acid, and kaempferol.
- Most of these have anti-cancer properties, and reduce the risk of occurrence of cancers of the cervix, colon, ovaries, breasts, and prostate.
- Lutein is beneficial for vision, and prevents macular degeneration, cataracts, and photophobia.
- Lipoic acid is an organosulfur compound that acts as an antioxidant. It also prevents cardiovascular diseases, degenerative brain diseases such as Alzheimer's, and chronic diseases associated with oxidative stress.
- Glucosinolates aid in the detoxification process of the body. They also contribute to a healthy lining of the stomach by checking bacterial overgrowth.
- Caffeic acid and ferulic acids act as antioxidants, which destroy the free radicals generated in the body. Caffeic acid also has anti-inflammatory properties.
- Kaempferol is known to reduce the risk of cardiovascular diseases and cancer.
Collard greens are a rich source of a number of vitamins and each of them has its own share of health benefits. These are vitamin A, vitamin K, B vitamins, vitamin C, and vitamin E.
- Vitamin A prevents heart ailments and cancer, in addition to improving our vision. In collard greens, vitamin A is present in the form of beta-carotene and has antioxidant properties.
- The vegetable also contains high levels of vitamin K, which plays a key role in coagulation of blood. It also helps prevent degenerative brain diseases, and is essential for the strengthening of bones.
- The various B vitamins include thiamine (vitamin B1), niacin (vitamin B3), pantothenic acid (vitamin B5), pyridoxine (vitamin B6), riboflavin (vitamin B2), and folates (vitamin B9). These vitamins promote cardiovascular health. Folates help in the production of RBCs and also in the functioning of neurons.
- Vitamin C and vitamin E act as powerful antioxidants. Vitamin C also acts as a natural antihistamine.
Collard greens contain minerals such as calcium, manganese, magnesium, sodium, potassium, iron, zinc, and phosphorous.
- Calcium is essential for healthy bones, and prevention of degenerative bone diseases, such as osteoporosis.
- Manganese acts as an effective antioxidant.
- Magnesium helps regulate smooth functioning of muscles, and strengthens the immune system. It is also essential for the functioning of nerve cells, and for strengthening of bones.
- Sodium and potassium are electrolytes that are essential for the regulation of blood pressure and blood volume.
- Iron is one of the most essential minerals, as it is a constituent of hemoglobin, which is the oxygen-carrying component of the blood. It is also used in the synthesis of proteins and enzymes in our body.
- Zinc plays a key role in DNA and RNA metabolism and gene expression.
- Phosphorous plays a key role in the formation of bones, and teeth. It is also an essential mineral for protein synthesis and production of energy molecules of adenosine triphosphate (ATP).
In spite of all the above-mentioned health benefits, collard greens should not be consumed in excess. In fact, the recommended quantity is 1½ cups a day, three times a week. Excess intake can lead to potential side effects, which are given as under.
- Collard greens may contain goitrogens that cause swelling of the thyroid glands. Thus, it should be avoided by those suffering from thyroid problems.
- The vegetable may contain oxalates, and so people suffering from oxalate kidney stones, should limit its intake.
- Due to the high amount of vitamin K, collard greens should be avoided by people who are taking anticoagulants.
This was all about the nutritive value of collard greens. While selecting these vegetables, ensure that the leaves are deep green in color with no signs of yellowing or browning. Also, note that smaller leaves are more tender and have a mild flavor. Although they are available all round the year, collard greens are at their best from January to April.