Have you ever tried kale? Kale is a superfood that offers a host of health benefits, and it deserves a place at anyone’s table. It is highly nutritious and is a great source of dietary fiber.
Here is everything you need to know about kale and why you should add it to your meal plan.
What is Kale?
Kale comes from the family of cruciferous vegetables, well known for their cancer-fighting properties. This crucifer is most closely related to the Acephala group of the species Brassica oleracea (oleracea var). Kale is already a popular health food, consumed in a variety of different ways. History shows that the ancient Romans and people of the Middle Ages included kale in their diet.
There are two main types of kale: one that has purple leaves and one that has green. The central leaves never form a head, which is why kale is thought to be more akin to wild cabbage than other domesticated types of vegetables such as spinach.
Kale is classified by leaf type:
- Curly, also known as Scots kale.
- Leaf and spear, a hybrid of curly and plain varieties.
- Cavolo nero, also known as dinosaur kale or black cabbage.
The most common variety of kale that you will find on the shelf of your local health food store is curly kale. This variety has curly, green leaves with a tough, fibrous stem. (1)
Kale Nutrition Facts
One cup of uncooked kale (2.4 ounces or about 65 grams) contains:
- 33 calories, (2 of which are fiber), 3 grams of protein and 6 grams of carbs.
- Vitamin C: 134% of the RDA.
- Vitamin A: 206% of the RDA
- Vitamin K: 684% of RDA.
- Vitamin B6: 10% of RDA.
- Manganese: 25% of RDA.
- Copper: 10% of RDA.
- Calcium: 9% of RDA.
- Magnesium: 6% of RDA.
- Potassium: 9% of the RDA.
Kale contains more than 3% of the RDA for Vitamin B1/Thiamin, Vitamin B2/Riboflavin, Vitamin B3/Niacin, phosphorus and iron. The fat found in kale comes from omega 3 fatty acids called alpha-linolenic acid (ALA). Kale has a low-calorie count per serving and yet it is still considered one of the most nutritious foods around. (2)
Healthy Compounds in Kale
Regularly consuming kale in your diet will have a dramatic impact on your health. The broad range of antioxidants found in this dark leafed crucifer has anti-viral, anti-inflammatory, and anti-microbial properties.
Kale is rich in the antioxidant quercetin, used to treat the common cold. The carotenoids Zeaxanthin and Lutein concentrate in the eye, preventing optic disorders such as cataract and macular degeneration.
Kale also contains large amounts of the carotenoid, beta-carotene, as well as various polyphenols and flavonoids. The antioxidant compounds reduce the presence of free-radicals in the blood. Free radicals are responsible for oxidative cell degeneration and death. Kale keeps the wrinkles out of your face and smile.
The flavonoids kaempferol and quercetin, are found in substantial amounts in kale. Nutritional science has extensively studied these compounds. Research shows that these substances have protective properties for every biological system in the body. (3)
4 Health Benefits of Kale
#1: Kale has anti-inflammatory and antioxidant properties.
The most beneficial property of consuming kale in your diet is its anti-inflammatory ability. With an ideal omega-3 to omega-6 ratio, kale is kind to your GI tract. The omega-6-rich processed foods found in the modern diet cause a chronic inflammatory response on a widespread scale across all biological systems in the body. Recent research in nutritional science shows that almost every disease known to man is linked to inflammation, from Crohn’s disease to rheumatoid arthritis, and cancer. Kale contains high amounts of anti-oxidant compounds that go to work in reducing inflammation and fight off free-radicals. (4)
#2: Kale promotes a healthy cardiovascular system.
Eating more kale will make your heart happy. The dark colors of the kale leaf suggest that it is nutrient dense and rich in vitamins and minerals. The combination of antioxidants and anti-inflammatory properties improve lipid balance. Bad LDL cholesterol lowers and the production of good, heart-friendly, HDL improves. The antioxidants also lower total lipid levels in the blood, reducing the risk of heart disease. (5)
#3: Kale has detoxification properties.
Kale is a natural detoxifier. This cruciferous vegetable is high in fiber and sweeps your GI tract clean. The soluble fiber found in kale removes any undigested food, toxins, and impurities from the digestive tract.
The isothiocyanate compounds (ITCs) found in kale, come from glucosinolates which help detox your liver at a cellular level. Toxins in our environment from, pesticides, pollutants, and pharmaceuticals, increase toxicity levels in the body, increasing the chances of contracting a disease. ITCs fight off toxins and assist in the removal of free-radicals. (6)
#4: Kale may help assist in the prevention of cancer.
The high-levels of antioxidants in kale can assist in the prevention of cancer. The cancer-fighting properties of cruciferous vegetables The immune-enhancing benefits of kale are a result of several compounds like indoles including indole-3-carbinol (I3C), di-indolemethane (DIM), and isothiocyanates, derived from glucosinolates. (7)
Kale for Paleo and Ketogenic Diets
Kale is a perfect fit for both the paleo and ketogenic diet. The cruciferous vegetable offers a nutrient-dense source of vitamins and minerals that keep the metabolism and immune system optimized at all times.
However, it is very important to understand the source of your kale. Deal only with sustainable farms that offer organic produce, guaranteed to be free from pesticides and other chemicals. When you purchase your kale, give it a thorough wash under running water to remove any organic residue.
Since kale is a crop grown in low-temperatures and it develops a delicious sweet taste in frosty climates. The freshest kale is found at farmers’ markets in the late fall and early winter time. Kale is also easy to grow and if you have space at home, why not plant a row of it?
What’s the Best Way to Eat Kale?
Cruciferous vegetables do not digest well when consumed raw. Kale is no different; it requires cooking to release the antioxidant compounds and break down the goitrogens. Goitrogens are linked to the excessive overgrowth of the thyroid gland. However, it should be noted that one would have to consume enormous amounts of raw kale to experience any adverse health effect from goitrogens.
It’s best to boil kale for three minutes before serving it. Cooking kale this way will not diminish the bioavailability of the valuable antioxidants, vitamins, and minerals. However, the brief cooking time will break down over 90% of the goitrogens and make your kale safe to eat. (8)
Potential Drawbacks of Consuming Kale
A popular breakfast health trend is the power green smoothie, made of kale. As we have mentioned, it’s a bad idea to consume cruciferous vegetables in their raw form. Therefore, it might be best to back off of the morning power smoothie or replace kale with another ingredient.
The goitrogens found in kale can be hazardous to your health when ingested in large amounts. Goitrogens can inhibit the conversion of iodine into thyroid hormone, a process that can’t be reversed.
Raw kale contains oxalic acid, which binds with minerals such as magnesium and calcium, causing crystallization. The crystals can damage tissue and create inflammation, leading to adverse health disorders such as kidney stones.
Some animals can handle a high oxalate intake in their diets because they typically have a genetic adaptation to eating kale, as well as help from bacteria to diminish the oxalate. However, most people living a western lifestyle do not have these bacteria in their gut. This means that consuming significantly large portions of cruciferous vegetables that are rich in oxalate, could land you a series of visits to the hospital for dialysis. (9)
Toss the kale shake and cook your crucifers to ensure the optimal absorption of vitamins, minerals, and antioxidants.
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