Kale – The true superfood. But does kale really live up to this superfood label? The answer is: yes, it does! Here is everything you need to know about Kale, also some of its impressive benefits, and some easy ways to incorporate kale into your diet beyond salads and smoothies.
Kale as we know it today was first cultivated in the Mediterranean region over 2,000 years ago. It played an important role in the food supply of Europe through the time of the Roman Empire and during the medieval period in Europe between the 5th and 15th centuries.
European colonizers are believed to have brought the first kale to North America in the 1600’s, and Russian traders are believed to have first brought this vegetable to Canada a century or so later.
Several thousand farms in the United States grow kale on a commercial basis, primarily in California, Georgia, New Jersey, and Texas. Compared with its fellow cruciferous vegetable, broccoli, total kale acreage is low, and between 5,000-7,500 acres. (For comparison, broccoli acreage is noted to be 130,000-150,000 acres.)
The cool-season nature of kale can sometimes be reflected in its flavor. When exposed to frost, kale can sometimes take on a sweeter taste (that is due to the conversion of some kale starches into sugars). Overall, however, the taste of kale can be surprisingly varied, from bitter or peppery to plainer and slightly sweet.
The three types of kale that we have become familiar with in the produce section of today’s grocery stores are actually domesticated versions of wild plants that took farmers hundreds of years to develop.
These three types include (1) flatter, wider-leafed kale, (2) darker Lacinato-type kale, and (3) more tightly formed, curly leafed kale. The list below shows some common kale varieties belonging to each of these three types:
(1) Flatter, Wider-Leafed Kale
- Smooth German
- Red Russian
- Black Magic
(2) Darker, Lacinato-Type Kale (also sometimes called Napus or Siberian type kale)
- Tuscan Black
- Dinosaur Kale
(3) More Tightly Formed, Curly-Leafed Kale (also sometimes called Scotch or Scotch-curled kale)
- Dwarf Blue Curled
Of course, there are not always sharp dividing lines between these three types of kale, and you can expect to find varieties that blend different features. Regardless of variety, however, all versions of kale are considered cruciferous vegetables and belong to the Brassica genus of plants that also includes bok choy, broccoli, Brussels sprouts, cabbage, cauliflower, collards, mustard greens, and turnip greens.
Kale is packed with nutrients
Kale is one of the most nutrient-dense foods on the planet, meaning it packs a powerful nutritional punch per typical serving. One cup of kale provides more than 100% of the daily minimum target for immune-supporting vitamin C and over 200% for vitamin A.
The latter nutrient also supports immunity, as well as skin and brain health. Additionally, kale contains smaller amounts of key minerals, including potassium, calcium, magnesium, manganese, iron, copper, and phosphorus. It also supplies energy-supporting B vitamins and some plant-based omega-3 fatty acids and plant protein.
Kale promotes bone health
Kale is a top source of vitamin K, with one cup packing nearly 700% of the daily goal. In addition to helping blood to clot, this key nutrient protects bones. Vitamin K is required for bone formation, and several studies have shown that a shortfall is linked to increased fracture risk and osteoporosis.
It keeps inflammation at bay
Kale is a potent source of antioxidants known to reduce inflammation, a trigger of premature aging and disease. Antioxidants also counter oxidative stress, which occurs when there is an imbalance between the production of cell-damaging free radicals and the body’s ability to counter their harmful effects. For these reasons, kale is thought to be one of the top disease-fighting foods.
Kale protects the heart
Kale has been shown to reduce cholesterol by increasing its excretion and preventing cholesterol from being reabsorbed from the digestive tract into the bloodstream. In one study in men with high cholesterol, the consumption of kale juice daily for 12 weeks increased “good” HDL cholesterol by nearly 30% and decreased “bad” LDL by 10%, while improving antioxidant status. Kale also helps fend off damage to artery walls, especially within the bends and curves most vulnerable to inflammation and hardened plaque buildup.
Kale helps reduce cancer risk
What we have already seen in the health research on kale is ample evidence that its glucosinolates provide cancer-preventive benefits.
Kale is a top food source for at least four glucosinolates, and once kale is eaten and digested, these glucosinolates can be converted by the body into cancer preventive compounds.
Kale’s glucosinolates and the ITCs made from them have well-documented cancer preventive properties, and in some cases, cancer treatment properties as well.
At the top of the cancer-related research for kale are colon cancer and breast cancer, but risk of bladder cancer, prostate cancer, and ovarian cancer have all been found to decrease in relationship to routine intake of kale.
Antioxidant-related health benefits of kale
Kale has been studied more extensively in relationship to cancer than any other health condition. This research focus makes perfect sense.
Kale’s nutrient richness stands out in three particular areas: (1) antioxidant nutrients, (2) anti-inflammatory nutrients, and (3) anti-cancer nutrients in the form of glucosinolates. Without sufficient intake of antioxidants, our oxygen metabolism can become compromised, and we can experience a metabolic problem called “oxidative stress.”
Without sufficient intake of anti-inflammatory nutrients, regulation of our inflammatory system can become compromised, and we can experience the problem of chronic inflammation.
Oxidative stress and chronic inflammation—and the combination of these metabolic problems—are risk factors for development of cancer. We’ve seen research studies on five specific types of cancer—including bladder cancer, breast cancer, colon cancer, ovarian cancer, and prostate cancer—and intake of cruciferous vegetables (specifically including kale). As a group, these studies definitely show cancer preventive benefits from kale intake, and in some cases, treatment benefits as well.
Kale’s cancer preventive benefits have been clearly linked to its unusual concentration of two types of antioxidants, namely, carotenoids and flavonoids. Within the carotenoids, lutein and beta-carotene are standout antioxidants in kale. over 45 different flavonoids have been identified in kale.
Most prominent among kale’s flavonoids are its flavonols, including kaempferol, quercetin, and isorhamnetin. Researchers have actually followed the passage of these two carotenoids in kale from the human digestive tract up into the blood stream, and they have demonstrated the ability of kale to raise blood levels of these carotenoid nutrients.
That finding is important because lutein and beta-carotene are key nutrients in the protection of our body from oxidative stress and health problems related to oxidative stress. Increased risk of cataracts, glaucoma, atherosclerosis, and chronic obstructive pulmonary disease (COPD) are four such problems.
Also, among these chronic health problems is cancer since our overall risk of cells becoming cancerous is partly related to oxidative stress.
Within the flavonoids, kaempferol is a spotlight antioxidant in kale, followed by a flavonoid called quercetin. You’re likely to be getting about 60 milligrams of kaempferol in the one-cup serving of kale that we use as the standard serving size on our website, as well as 29 milligrams of quercetin.
Alongside of these spotlight flavonoids, however, it is probably the very broad spectrum of flavonoid antioxidants in kale that are largely responsible for kale’s cancer-preventive and other benefits, owing to their ability to reduce oxidative stress.
Kale supports eye health
The antioxidants zeaxanthin and lutein in kale protect the retina and lens. They’ve also been shown to reduce the risk of macular degeneration and cataracts, two common eye disorders.
It’s friendly on the figure
One cup of kale provides roughly 10 to 30 calories, depending on how loose or packed it’s prepared. Its water and fiber content make it filling—so you can cut back on more caloric foods. For example, trading one cup of cooked brown rice with one cup of chopped kale and a half cup of the rice increases total food volume while saving about 85 calories and 20 grams of carb.
How to consume more kale
You can serve eggs over kale for a breakfast salad, or add kale to an omelet, scramble, or frittata. Sprinkle finely chopped kale over oatmeal or overnight oats and blend a handful into any type of smoothie.
Bake kale in the oven for a crispy snack or a topping for just about any dish. Gently massage kale with extra virgin olive oil or avocado oil as the base for a salad, bed for your protein, or a tasty green to blend with whole grains. Add kale to soups; chili; stews; stuffed peppers; hummus or other dips; and casseroles. Toss shredded kale onto pizza and tacos.
Whip the leafy green into the wet ingredients when you make pancakes or other baked goods. Or stir finely minced kale into nut butter, energy balls.
The research track record for kale in providing overall cardiovascular support is fairly strong, and not limited to improvement in blood cholesterol levels. However, research on kale and cholesterol levels is especially interesting.
Recent studies show that kale can provide you with some special cholesterol-lowering benefits if you cook it by steaming. The fiber-related components in kale do a better job of binding together with bile acids in your digestive tract when they’ve been steamed. When this binding process takes place, it’s easier for bile acids to be excreted, and the result is a lowering of your cholesterol levels.
Raw kale still has cholesterol-lowering ability—just not as much. Along these same lines, a recent study has examined the impact of 5 ounces of kale juice per day for 12 weeks in men with high blood cholesterol levels (above 200 mg/dL). Consumption of kale juice was determined to raise the HDL levels in these study participants, lower their LDL levels, and also improve their atherogenic profiles (which measured their likelihood of developing coronary artery disease).
kale is a food that you can count on for some outstanding health benefits, if for no other reason than its exceptional nutrient richness. So many benefits not to be taking. If you aren’t already taking Kale, start today and watch and feel the benefits of this, Kale – The true superfood.