What Is Kale? A Guide on Kale Nutrition and Its Benefits

It seems like kale is the superfood of the century but if you still haven't tried it, you’re not alone in wondering, what is kale? Here’s a guide on kale nutrition and the benefits of kale.

At this point, everyone's heard of kale. But not everyone has tried it—and if you're one of the people wondering, "What is kale?" we have all the answers. A member of the cabbage family, kale is a leafy green that’s related to Brussels sprouts, broccoli, and other cruciferous veggies that's been growing in popularity thanks to its wide variety of health benefits and high concentration of vitamins, minerals, and fiber.

What Is Kale?

In the past, American farmers grew kale leaves largely as a garnish, but it’s been a popular vegetable throughout Europe and other parts of the world like Asia, South America, and Africa since before the Middle Ages. Over the last few years in the US, kale has made its way from serving as décor under bowls of iceberg to the top of salad bar offerings, thanks to health experts promoting it as a fantastic source of nutrients and antioxidants. Today, the majority of kale grown in the US comes from California farms, with Georgia, New Jersey, and Texas following not too far behind.

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Types of Kale

There are as many types of kale as there are ways to prepare this delicious leafy vegetable, and it comes in a range of colors from deep green and purple to even white and pink. Unlike its relative the cabbage, kale doesn’t grow in a round head, but in long stalks similar to romaine lettuce. The most common variations of kale include curly, purple, and Dinosaur or Lacinato kale.

Curly Kale features dark, thickly ruffled leaves and is a sturdy, earthy green with a peppery edge to it that tends to be bitter when eaten raw. If you prefer less bitterness, choose baby kale as it has a milder flavor.

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Redbor or purple kale is distinctive from other kales thanks to its deep purple stems and its vibrant, frilly leaves in shades of red and maroon. Eaten raw, it has a mild cabbage-like flavor and a hearty texture that becomes softer and sweeter when cooked.

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Dinosaur or Lacinato Kale, also known as Tuscan Kale, has been a staple in Italian cuisine for centuries. Also called cavolo nero ("black cabbage” in Italian), it has long, dimpled blue-green leaves (reminiscent of reptile skin) and is more delicate and less bitter than curly kale.

Kale vs. Spinach

While kale is a member of the cruciferous (brassica) family of vegetables, spinach is related to beets and its taste is less aggressive than kale. Although they’re both high in nutrients and good for you, when it comes to the many of the health benefits of kale vs. spinach, kale packs a bigger punch with higher levels of Vitamins B6 and K. Plus thicker, heartier kale lasts longer in your fridge than more delicate spinach.

Benefits of Kale and Kale Nutrition

The health benefits of kale are among the highest of any food around. Kale benefits include the fact that it’s quite high in nutrients and provides over 100% of the RDA of several vitamins including A, K, and C. But the benefits of kale don’t stop there!

Kale is a powerful source of antioxidants.

Antioxidants protect our bodies from free radicals, which are linked to cancer, blood vessel diseases, and other health issues. The flavonols kaempferol and quercetin are among the top antioxidants found in kale, two cartotenoids that may protect our body from health problems such as cataracts, glaucoma and chronic obstructive pulmonary disease (COPD).

Kale helps reduce the risk of heart disease by lowering cholesterol.

Researchers have learned that adding kale to your diet on a regular basis can increase your HDL or “good” cholesterol while simultaneously lowering your LDL (“bad” cholesterol) levels.

Kale is packed with a variety of cancer-fighting substances.

Kale has been shown to contain a range of compounds that are believed to protect our bodies from forming cancer cells. Sulforaphane and indole-3-carbinol are just two of the anticarcinogenic agents (cancer inhibitors) found in kale’s makeup.

Kale supports cardiovascular health.

Thanks to its high levels of antioxidants and anti-inflammatory nutrients, kale helps us avoid clogged arteries and plaque build up in our circulatory system. That along with its cholesterol-lowering powers makes kale a heart-healthy food.

Kale is a great weight-loss friendly vegetable.

Because kale is a hearty green with few calories, eating it helps you feel full without packing on pounds. On top of that, the fiber contained in kale’s leaves are effective agents in promoting weight loss.

How to Prepare Kale

Now that you’ve learned about how great this leafy green is for your health (and your waistline), you’re probably wondering how to prepare kale. Kale can be eaten raw in salads, but it’s also delicious when sautéed, steamed, or even baked into crisps that are a fantastically crunchy substitute for potato chips.

Enjoy it raw.

Although it’s one of the few vegetables that is healthier when cooked, kale still packs a wallop nutrient-wise when it’s eaten raw like in a kale Caesar salad or as an ingredient in our surprisingly delicious Kale-Apple Smoothie.

Add it to stir-fry dishes.

Remove the tough spines and chop or cut the kale leaves into strips for a great addition to stir fries like this beautiful, vegetarian Kale With Roasted Peppers and Olives.

Try it boiled.

The hearty leaves of kale soften with boiling, yet keep their beautiful color, making it a wonderful addition to dishes such as this super yummy Kale Colcannon.

Sauté it.

Kale is a great choice for sautéed side dishes because the leaves don’t get limp like other greens. Check out this tasty version that includes Brussels sprouts and crisp fried capers.

Use it in soups and sauces.

A robust addition to any soup or stew, kale is also great in pasta sauces and can even be blended into a delicious pesto like with our Cheese Ravioli With Kale Pesto and Roasted Carrots.

Can You Freeze Kale?

If you’re not going to use your kale right away, you may wonder, can you freeze kale? In a word, yes! Learning how to freeze kale is a simple way to avoid tossing piles of yellowed, wilted leaves, and it gives you easy access to a healthy ingredient for your smoothies or sautés. Note that once it’s frozen, kale’s texture changes, so stick with fresh kale for salads.

To prepare your kale for freezing, you want to wash the leaves and remove the thick stems (which can be frozen separately for use in soups or stews where they’ll be cooked down more), but don’t worry about blanching. All you need to do is roughly tear or chop the leaves and then quickly freeze them in small clumps on a cookie sheet. Once they’re frozen, store the clumps in freezer bags until you’re ready to grab a handful for a recipe. Don’t worry about thawing. Frozen kale can go straight from the freezer into your morning smoothie or your evening entrée.