Pitched as a ‘superfood’, kale is very popular in 2017. Despite this there are still many people who are not fond of kale and seldom (if ever) eat it. This may be because they have never experienced how tasty kale can be when properly prepared in a delicious recipe. If you are ‘kale shy’ we are going to have a go at convincing you to try it – without kale in your diet – you are missing out on numerous health benefits.
Kale is a member of the cruciferous vegetable family which is renowned for its many healthy compounds and outstanding health benefits, not least of which is their ability to fight and prevent cancer. Other members of this vegetable family include arugula, bok choy, broccoli, Brussels sprouts, cabbage, cauliflower, mustard greens, radish, turnip, and watercress.
The History of Kale
Kale was one of the most common green vegetables in Europe until the end of the Middle Ages. Russian kale was introduced into the United States in the 19th century by traders. Cultivation of kale was encouraged in the UK during World War II by the ‘Dig for Victory’ campaign because it was easy to grow and it provided such dense nutrition to supplement what was often missing due to food rationing.
Today, kale appears on many superfood lists. It is highly nutritious, containing high levels of vitamins, minerals, and brain-boosting and health-enhancing phytonutrients. Kale is also one of the easier crops to grow in domestic gardens and by small farmers.
Kale is especially high in vitamins K, A, and C. It contains more than 1,000 percent of the recommended daily intake of vitamin K, 98 percent of vitamin A, and 71 percent of vitamin C (more than an orange). Kale is also a great source of calcium, magnesium, iron, and antioxidants.
It contains abundant antioxidants which help remove free radicals from the body which can lead to accelerated aging as well as cancer and other serious diseases. It only takes 100 calories of kale to provide over 350 milligrams for the most basic omega-3 fatty acid (alpha-linolenic acid, or ALA).
Health Benefits of Kale
Kale provides comprehensive support for the body’s detoxification system. New research has shown that the isothiocyanates (ITCs) made from kale’s glucosinolates can help regulate detox at the cellular level.
Good Heart and Cardiovascular Health
Kale has a good balance of omega-3 and omega-6 fatty acids, essential for heart health. Kale is also an excellent source of potassium, another must for heart health. Vitamin K, also associated with heart health because it is an essential factor in blood clotting and a lack of it can cause hemorrhages. In addition, a lack of vitamin K may cause mechanisms that stop the formation of blood vessel calcification to become inactive.
Kale aids the management of diabetes in a number of ways. Its sulfur content aids diabetes with a role in detoxification as well as the production of glutathione, one of the body’s most important antioxidants. Sulfur is also extremely important for glucose metabolism, helping to decrease weight gain and the risk of diabetes. One study found that kale contained more glucoraphanin, the precursor to sulfur, than broccoli.
One cup of cooked kale contains 10% of your daily fiber needs. Increased fiber can reduce blood glucose levels shown in the standard fasting blood glucose test (a test of blood sugar levels after an overnight fast). Increased fiber also decreases glycated haemoglobin (HbA1c) levels. These levels indicate when proteins in the blood mix with blood sugar, and are associated with increased risk of diabetes complications.
Brain Boosting Power
Kale has at least 45 different flavonoids and their regular intake may help reduce the risk of stroke. It also contains significant iron, which helps in the formation of hemoglobin, the main carrier of oxygen to cells of the body, including the brain. The omega-3 fatty acids are also important for brain memory, performance, and behavioral function. The compound sulforaphane found in kale has anti-inflammatory properties that may help cognitive function, especially after a brain injury.
Lowering Cholesterol Levels
Kale has a high fiber content which helps lower cholesterol levels by picking up excess cholesterol compounds in the gut and pushing them out in the elimination process. Research has found that the fiber in steamed kale binds better to bile in the digestive tract, resulting in greater removal of cholesterol.
Building Better Bones
Kale is listed as one of the “good-for-your-bones foods” by the National Osteoporosis Foundation because of its calcium content. One cup of cooked kale has about the same amount of calcium as one cup of cow’s milk.
Skin and Hair Health
The sulfur in kale helps in removing toxins from the skin, boosts the production of collagen (which keeps us looking youthful), and aids in wound healing and reducing of scarring. The vitamin C in kale is also necessary for collagen production. Kale is high in vitamin A, a compound in retinoids, also popular in anti-aging skin treatments. The iron in Kale may help prevent hair loss because iron deficiencies can cause hair loss.
Weight Loss and Maintenance
There’s just 33 calories in each cup of kale. It makes a popular and nourishing food for those reducing calories. It is also a good source of magnesium, one of the minerals that many of us are deficient in − kale supports the body in maintaining optimum digestion as well as managing stress.
Kale is an exceptional to support lowering the risk of chronic inflammation. Many of the compounds in kale, such as vitamin K, are key nutrients for helping regulate the body’s inflammatory process. Inflammation often plays a key role in the development of cancer, particularly chronic inflammation.
Kale is a very good source of the antioxidants lutein, beta-carotene, kaempferol, and quercetin − all of which are associated with cancer prevention and treatment benefits. Like other members of the cruciferous vegetable family, kale is rich in sulfur-containing compounds called glucosinolates which support detoxification, and indole-3-carbinol which greatly reduces the risk of breast, colon, and lung cancer.
Research suggests that kale may be most helpful in protecting against bladder, breast, colon, ovary, and prostate cancers. A study published in the journal Molecular Cancer found that that sulforaphane glucosinolate stopped growth in epithelial ovarian cancer cells. Numerous other studies have been performed on kale which show cancer preventive benefits from kale intake, and in some cases, treatment benefits as well.
The cancer preventive benefits of kale have been linked to the high concentration of two types of antioxidants − carotenoids and flavonoids. Within the carotenoids, lutein and beta-carotene stand out. Lutein and beta-carotene are key nutrients for protecting the body from oxidative stress. The most prominent of kale’s may different flavonoids are the flavonols, including kaempferol, quercetin, and isorhamnetin. The glucosinolates found in kale are utilized for DNA repair and help prevent cancer and slow the growth of cancer cells.
Is it Safe to Eat a Lot of Kale?
Kale contains oxalate, a naturally-occurring substance found in food, including leafy vegetables. There are cautions that eating leafy green food with a high oxalate level may cause kidney stones by increasing the concentration of calcium or oxalate in urine, causing stones to form. However kale, unlike many other leafy vegetables, has a very low oxalate level. That means that the calcium and iron found in kale are highly digestible.
If you eat a lot of other leafy vegetables which are higher in oxalate levels, you can minimize your oxalate intake risks by chewing well and relaxing between meals.
After the New York Times published an opinion piece in January of 2014 about possible connections between kale (and other cruciferous vegetables) and thyroid problems, kale has come under suspicion for being goitrogenic – the term used for a substance that could cause swelling or dysfunction of the thyroid gland. However, recent studies have shown that kale and other cruciferous vegetables do not interfere with thyroid function in healthy people. According to an article in The Permanente Journal, even people with hypothyroidism can eat as much kale as they want if it is cooked.
Pesticides and Kale
It is highly recommended that you choose organic kale whenever possible and be sure to wash it thoroughly. Conventionally grown kale can contain high levels of pesticide residue.
A simple and cheap veg wash can be made by leaving kale soaking for up to half an hour in a large bowl of water and a cup of white vinegar. Hydrogen peroxide can be substituted for the vinegar. Some people spray a combination of white vinegar and hydrogen peroxide on produce and then rinse with running water.
The way you prepare and cut your kale will affect how much you enjoy your ‘green packed’ meal. Cutting kale leaves into 1/2″ slices and the stems into 1/4″ lengths, then steaming for 5 minutes helps ensure quick and even cooking. There is a belief that there are potential health benefits from letting the stems and slices sit for about 5 minutes prior to cooking.
How can you incorporate more kale into your diet? Massaging it with a bit of olive oil and sea salt as the base of a green salad is the first ‘stand by’ technique. Blending it into smoothies, soups, or sauces adds lots of extra green into a meal, you can sauté it with other vegetables into a stir-fry, bake it into frittatas, lasagnas, or burgers − and dehydrate or slow bake it into kale chips.
Kale is simply too healthy to leave out of your diet. By getting creative preparing it and combining it in recipes you may find you crave the good green leaf and all the nutrition it offers.