Health Benefits of Kale
Everyone seems to be talking about green smoothies, superfood shakes and vegetable juices nowadays. And no wonder; people are discovering all over the world that they help curb unhealthy cravings, boost their immunity and are even a fantastic meal replacement for busy folks on the go.
And what is one of the most common ingredients in these “green” superfood concoctions?
Rich in vitamin K, vitamin A and vitamin C along with other vital nutrients, the health benefits of kale include detoxification, heart support, cancer prevention and a number of others covered in this article.
Health Benefits of Kale in History
A member of the illustrious group of cancer-fighting cruciferous vegetables, kale is quickly becoming one of the most popular health foods today. Ornamental kale has also taken conventional landscapes by storm. With their brilliant blue, red and white interior, these varieties of kale are edible as well! (1)
The health benefits of kale have been enjoyed since ancient Rome and history tells us that it was one of the most popular green leafy vegetables of the Middle Ages.
Kale comes from the Acephala group of the Brassica oleracea species that includes collard greens. There are two main varieties of kale: one that has green leaves and one that has purple. Interestingly, the central leaves do not form a head, which is one reason why kale is considered to be more closely related to wild cabbage than most domesticated forms of vegetables. (1)
It is most commonly classified by leaf type:
- Cavolo nero (Dinosaur Kale, Black cabbage)
- Curly (Scots Kale)
- Leaf and spear (hybrid of curly and plain)
Being part of the Brassica oleracea vegetable species, kale is in good company and it shares many of the same characteristics as its cousins:
- Bok Choy
- Brussel Sprouts
- Mustard greens
When in doubt, eat cruciferous vegetables. Rich in glucosinolates, they all:
- Are anti-inflammatory
- Contain antibacterial and antiviral properties
- Inactivate carcinogens
- Reprogram cancer cells to die-off
- Prevent tumor formation and metastasis
Kale Nutrition Facts
In just one cup of chopped kale, you’ll find: (2)
- Vitamin K (684% recommended daily value)
- Vitamin A (206%)
- Vitamin C (134%)
- Manganese (26%)
- Copper (10%)
- Calcium (9%)
- Potassium (9%)
- Vitamin B6 (9%)
- Iron (6%)
- Magnesium (6%)
- Folate (5%)
- Riboflavin (5%)
- Thiamin (5%)
- Phosphorus (4%)
- Protein (4%)
- Niacin (3%)
- Zinc (2%)
- Pantothenic Acid (1%)
- Selenium (1%)
- Sodium (1%)
- Omega-3 fatty acids (121 mg)
- Omega-6 fatty acids (92.4 mg)
A rich source of several vitamins and minerals, the vitamin K content in one cup of cooked kale stands out considerably amongst the rest of the nutrients. Playing a key role in blood clotting and excessive bleeding prevention, some experts are now looking to vitamin K as a natural way to treat osteoporosis, but the research is conflicting so the medical profession hasn’t embraced it yet. (3)
7 Health Benefits of Kale
Of the health benefits that healthcare providers have accepted, these 7 stand out:
Arguably the most beneficial property of eating kale is its ability to be a powerful anti-inflammatory agent. When you consider the ideal omega-3:omega-6 ratio, kale is the “perfect food.” According to a study published in Biomedicine and Pharmacotherapy, (4)
“Several sources of information suggest that human beings evolved on a diet with a ratio of omega-6 to omega-3 essential fatty acids of approximately 1 whereas in Western diets the ratio is 15/1-16.7/1. Western diets are deficient in omega-3 fatty acids, and have excessive amounts of omega-6 fatty acids compared with the diet on which human beings evolved and their genetic patterns were established.”
Being “pro-inflammatory,” the omega-6 rich processed foods that many people live off of today cause a chronic inflammatory state on a widespread scale, which has been linked to nearly every disease known to man, such as rheumatoid arthritis, crohn’s, and cancer.
Kale, on the other hand, naturally promotes the pro-inflammatory omega-6 and anti-inflammatory omega-3 balance. Nearly at a 1:1 ratio, kale contains slightly more omega-3s, which can help reduce the negative effects that people experience when they eat omega-6 rich processed foods loaded with vegetable and canola oil.
Going hand-in-hand with its anti-inflammatory potency, kale is a marvelous antioxidant food. Of the three main antioxidant vitamins in the world, kale is particularly rich in vitamin C and beta-carotene (the precursor to vitamin A). (5)
This is important because antioxidants are known to counteract the damage caused by free radicals. (6)
Your body is exposed to highly unstable free radical molecules every day through the polluted air that we breathe, toxins in our food and chemicals in our water. These cause “oxidative stress,” a process that triggers cell damage and has been linked to everything from cardiovascular disease to cancer to cataracts.
Oxidative stress is also known to be one of the main contributing factor to neurocognitive disorders such as Parkinson’s disease, Alzheimer’s disease.
One of the top health benefits of kale is that it is a natural detoxifier. It not only helps remove toxins but also helps eliminate them from your body.
This is due to a component in kale called isothiocyanates (ITCs) which are made from glucosinolates. They have been reported to help detox your body at the cellular level. (7)
These ITC’s are a powerful “one-two punch” against toxins and free radicals. Toxins in our environment, such as processed foods, pollutants, pesticides, and pharmaceuticals increase the toxic level of the body and increase the chance of disease.
So removing the toxins from you body is an important job. Toxins are destroyed first by antioxidants, and then removed (detoxified) with glucosinolates. In the words of the George Mateljan Foundation, (7)
The two steps in the process are called Phase I detoxification and Phase II detoxification. The ITCs made from kale’s glucosinolates have been shown to favorably modify both detox steps (Phase I and Phase II). In addition, the unusually large numbers of sulfur compounds in kale have been shown to help support aspects of Phase II detoxification that require the presence of sulfur. By supporting both aspects of our cellular detox process (Phase I and Phase II), nutrients in kale can give our body an “edge up” in dealing with toxic exposure, whether from our environment or from our food.
This is important to our discussion on kale because, according to an article published in the International Journal for Vitamin and Nutrition Research, ITC’s stimulate the production of Phase II enzymes. The health benefits of kale are most potent the sooner you can get it after harvesting, as glucosinolates are easily dimished under certain conditions. In fact, (8)
“These compounds remain intact unless brought into contact with the enzyme myrosinase by pests, food processing, or chewing….Glucosinolates can be gained or lost by vegetables during storage. They may be degraded or leached during processing…”
So if your produce undergoes any sterilization or radiation treatment, this can greatly weaken the ITC’s that are available. This is why it is so critical to get your kale from a solid, responsible source such as a local farmer or organic grocery store.
Deirdre Orceyre, a naturopathic physician at the Center for Integrative Medicine at the George Washington University Medical Center, says that, “Any vegetable that has a very deep color the way kale does, that means there is a high concentration of nutrients, and that translates into a range of antioxidant and anti-inflammatory effects in the body.” (9)
This powerful antioxidant and anti-inflammatory duo in kale make it a perfect food for heart health.
According to registered dietitian and nutritionist Cheryl Harris, “Brassica vegetables are known to help with general health as well as heart disease and cancer, but even among this group kale stands out.” (9)
This is because kale has a very robust range of antioxidants and also significant levels along Vitamin K and a type of Vitamin E that seems to be heart-healthy, Harris says. It has even been shown to lower cholesterol in clinical studies and increases the HDL: LDL ratio by up to 27%! (10)
Another on of the key health benefits of kale is its ability to help in infant brain development in the womb. Kale is a valuable source of folate. So eating kale regularly can help prevent several birth defects and promotes:
- Adequate birth weight.
- Healthy neural tube formation.
- Proper development of the face and heart.
This is extremely important information for all women of childbearing age because most doctors push folic acid supplementation, which is a synthetic version of naturally occurring folate that has been linked to:
- Vitamin B12 deficiency
- Changes in sex drive
- Lack of focus
- Trouble sleeping
- Emotional ups and downs
Like all of cancer-fighting cruciferous vegetables, kale has been shown to stop cancer in its tracks. Studies have shown, for example, that more than 70% of all research conducted on cruciferous vegetables has found that they protect against cancer. (11)
According to the National Cancer Institute, for example, the secret behind the cancer-killing ability of cruciferous veggies is that they are rich in glucosinolates – a large group of sulfur-containing compounds. (12)
These powerhouse chemicals are known to break down during the chewing and digestion process into biologically active compounds that prevent cancer cells growth, which are referred to as indoles, thiocyanates and isothiocyanates.
Having been discovered to prevent cancer growth in rats and mice, indoles and isothiocyanates are heralded to protect against cancer of the bladder, breast, colon, liver, lung and stomach. There are several reasons why indoles and isothiocyanates stop cancer from spreading: (12)
- They inactivate carcinogens.
- They contain antiviral and antibacterial properties.
- They contain anti-inflammatory properties.
- They protect cells from DNA damage.
- They induce cell death (apoptosis).
- They inhibit tumor blood vessel formation.
- They inhibit tumor cell migration.
Another one of the amazing health benefits of kale is it can improve your eyesight! Two nutrients that give kale its dark green hue, lutein and zeaxanthin, have been shown to help prevent macular degeneration and cataracts.
Both lutein and zeaxanthin act as antioxidants in the eye and filter harmful high-energy blue wavelengths of light, the American Optometric Association (AOA) state that they literally help protect and maintain healthy cells.
According to the AOA, “Of the 600 carotenoids found in nature only two are deposited in high quantities in the retina (macula) of the eye: lutein and zeaxanthin.” (13)
It is easy to enjoy the health benefits of kale, since it is in so many great recipes! My two favorite ways of eating kale are by making these two amazingly delicious recipes: I like to drink my popular peachy super kale shake in the morning and munch on kale chips for a snack, especially when I’m on the go! Both are super easy to make and extremely tasty. Other way to cook with kale include:
- Steamed for a few minutes (making sure not to overcook them and denature the proteins).
- Shredded into thin slices and eaten raw in salads and as a garnish.
- Lightly sautéed with coconut oil, fresh garlic cloves and some onions.
Where you Buy Your Kale Matters!
The health benefits of kale greatly depend on the source you buy it from. Whenever you shop for kale, make sure to get organic kale as it is one of the most heavily pesticide-sprayed crops.
Two-thirds of produce sampled in recent evaluations were poisoned with pesticides and non-organic kale ranks amongst the world’s most heavily polluted crops. Known as the Environmental Working Group’s (EWG) “Dirty Dozen Plus” this list includes (1):
- Sweet Bell Peppers
- Nectarines (Imported)
- Cherry Tomatoes
- Snap Peas (Imported)
- Hot Peppers
Non-organic kale is one of the most deadly because (according to the EWG report), there were studies in 2007 and 2008, where USDA scientists found 51 pesticides on kale.
So, bottom-line, buy from a good source and always wash your produce thoroughly before eating it. If in doubt, cook it, as pesticides a re greatly reduced when cooking. (1)
Want to experience the health benefits of kale for yourself? Then check out my Quinoa Salad with Dark Cherries and Kale for a delicious way to get healthy!