Kale – properties and nutritional values
Kale is a vegetable whose nutritional and health properties were appreciated since antiquity. However, in Poland it is still used more for decorating platters than for eating. This is a huge mistake, because kale prevents many serious diseases such as cancer and heart disease.
Kale is a variety of cabbage with long, wrinkled leaves, the health properties of which are appreciated all over the world. The colorful leaves of the kale (in various shades of green, violet-green and violet-brown) are a treasury of protein, fiber, vitamins – mainly C and K, as well as mineral salts – especially calcium and potassium, and sulforaphane – a strong antioxidant.
Kale – anti-cancer properties
Kale, like broccoli and other cruciferous vegetables, is a treasure trove of sulforaphane – an antioxidant that has a strong anti-cancer effect. Sulforaphane can protect e.g. against cancer of the prostate, lung and colon. However, in order for the kale to retain as much of its anti-cancer properties as possible, it should be cooked similar to broccoli, i.e. steamed for a maximum of 3-4 minutes. Otherwise, it will lose its health-promoting effect.
Kale contains indoles that inhibit the secretion of active estrogens, thus also preventing breast cancer.
Kale – a wealth of polyphenols
In addition, kale contains carotenoids (beta carotene, lutein, zeaxanthin) – antioxidants that also inhibit harmful oxidative processes, and thus – can prevent the development of cancer. It has been proven that the consumption of carotenoids can reduce the incidence of cancers such as cancer of the mouth, larynx, esophagus and bladder.
It is worth knowing that the color given by carotenoids (i.e. yellow, orange or red) in kale is masked with chlorophyll – a green dye that also has an antioxidant effect and supports the body’s cleansing processes – it creates strong connections with some toxic compounds (including some carcinogenic substances) thanks to smaller amount of harmful compounds reaches the body’s tissues.
Kale is also a treasury of another anti-cancer substance – vitamin K, which also inhibits the development of certain cancers, including breast cancer, ovarian, colon, gallbladder and liver tumors. According to specialists from the Food and Nutrition Institute, its deficiency may result in an increased risk of cancer development.
Raw / cooked kale nutritional value (per 100g) based on USDA National Nutrient Database data
Energy value – 49/28 kcal
Total protein – 4.28 / 1.90 g
Fat – 0.93 / 0.40 g
Carbohydrates – 8.75 / 5.63 g
Fiber – 3.6 / 2.0 g
Vitamin C – 120/41 mg
Thiamin – 0.110 / 0.053 mg
Riboflavin – 0.130 / 0.070 mg
Niacin – 1,000 / 0.500 mg
Vitamin B6 – 0.271 / 0.138 mg
Folic acid – 141/13 μg
Vitamin A – 9990/13621 IU
Vitamin K – 704.8 / 817.0 μg
Calcium – 150/72 mg
Iron – 1.47 / 0.90 mg
Magnesium – 47/18 mg
Phosphorus – 92/28 mg
Potassium – 491/228 mg
Sodium – 38/23 mg
Zinc – 0.56 / 0.24 mg
Vitamins K and A are durable, heat-resistant vitamins, but frying reduces their amount. On the other hand, cooking does not cause the loss of these vitamins, it contributes to their release and therefore their content after cooking may be slightly higher.
Kale supports the work of the cardiovascular system
Kale contains large amounts of vitamins and elements that support the work of the cardiovascular system. The elements are dominated by potassium, which makes the blood vessels more permeable, which makes the blood circulate more freely (the effect is a drop in pressure), and calcium, which plays an important role in the proper pumping of blood to all body tissues.
Kale is a treasury of vitamin C. Only peppers and parsley have more of them.
In addition, along with potassium, calcium regulates blood pressure. Kale also contains vitamin C, which seals and strengthens blood vessels, inhibits the oxidation of “bad” LDL cholesterol, and thus – prevents atherosclerosis. In addition, it lowers blood pressure, participates in the production of red blood cells, which may prevent anemia.
In turn, vitamin K, which is also present in this vegetable, plays an important role in the blood clotting process, e.g. reduces excessive menstrual bleeding. Its deficiency may cause poor blood clotting, susceptibility to internal and external hemorrhages, and problems with wound healing.
Kale – where to buy?
The kale season begins in the fall and lasts almost all winter. The best leaves are dark green, firm, brittle, without stains or damage. Younger shoots are tastiest after frosts, because their leaves lose their sharp, cabbage flavor. Late winter kale perfectly tolerates frost, even down to -15 degrees C.
You can buy kale at some markets and supermarkets. You can also look for it in health food stores. After purchase, it’s best to keep it in the bottom of the refrigerator in a foil bag with holes, but only for 3 days. Alternatively, it can be frozen.
Kale – how to make it?
Kale can be prepared in a similar way to spinach, i.e. fried or blanched. In addition, kale will enrich the taste of salads and vegetable dishes with rice, porridge or pasta. Kale chips are also very famous. This green vegetable is also one of the ingredients of an Irish dish called colcannon. It is a type of potato purée with the addition of shredded kale or cabbage. In Ireland, colcannon is traditionally eaten on Halloween. Besides, kale can be eaten raw.
Kale can protect against ulcers
Kale can protect against gastric and duodenal ulcers. In this green vegetable, the above-mentioned Sulforaphane destroys Helicobacter pylori, bacteria that can contribute to the development of ulcers, as well as a number of other disorders, including gastritis.
Kale for healthy eyes
Kale has a lot of beta-carotene, from which the body produces vitamin A – a compound that is involved in the process of seeing – including preventing the so-called. night blindness, problems with vision at twilight, and dry eye syndrome. In addition, kale contains other antioxidants such as lutein and zeaxanthin, which are the main components of the macular pigment. Their antioxidant effect is based on the fact that they protect the retina of the eye against damage by free radicals and the harmful effects of excess light energy. Vitamin C has similar antioxidant properties.
Kale: Uses, Side Effects, Interactions, Dosage, and Warning
Kale, like other cruciferous vegetables, provides a lot of goitrogens – compounds that can affect the metabolism of iodine, leading to a reduction in its concentration in the body, which leads to a disturbance in the synthesis of thyroid hormones and gland hyperplasia.
Kale causes gas and gas, especially when raw. The cooked one is less bloating.
Fortunately, they can be limited to some extent by cooking (goitrogens are released under the influence of high temperature). Nevertheless, people with thyroid disease should avoid kale and other cruciferous vegetables.
Kale contains oxalates!
Kale, next to beetroot, spinach and rhubarb, is a product rich in oxalates, therefore it should be avoided by people struggling with oxalate stones.