Kale is considered one of the healthiest foods around. It is one of the cruciferous vegetables, and has been directly linked to several important health benefits. Eating a cup of kale each day has been shown to have a very real impact on your risk of being diagnosed with cancer, on your cardiovascular health, on your eye health, and more.
What Is Kale?
Kale is a nutritionally dense vegetable that was first grown in the Mediterranean centuries ago. It was such an important food in Europe that when explorers began venturing around the world, they brought it with them. That is how it began to be grown in North America back in the 1600s. It is now farmed and grown wild.
Kale is a member of the Brassica family of vegetables. Brassica are the cruciferous vegetables, which are known for their high levels of anti-cancer compounds. Other cruciferous vegetables include cabbage, Brussels sprouts and broccoli, but kale may be the healthiest of them all. It contains more lutein, a carotenoid, than any other food, as well as high levels of fiber and flavonoids.
Though there are many different varieties of kale, including those that grow wild, the three types that are most commonly found in produce markets are the flat, wide-leaved types; the darker Lacinato type that was originally grown in Italy; and the curly-leaved type. There are several varieties within each category:
- Wide-Leafed Kale
- Beria
- Black Magic
- Red Russian
- Smooth German
- Tronchuda
- Lacinato Kale
- Dinosaur
- Toscano
- Tuscan Black
- Curly-Leaf Kale
- Darkibor
- Dwarf Blue Curled
- Starbor
- Winterbor
The three categories of kale all have varietals that grown in different colors and nutritional value. There can be a wide disparity in the number of flavonoids between one type and another, but studies have shown that the darker types and those with curlier leaves tend to have higher levels of some of the most beneficial compounds.
1. Kale is a Low-Calorie Food that Contains a Remarkable List of Nutrients
Kale is a rich source of several important vitamins and minerals, as well as other nutritional compounds that have been shown to have huge health benefits. Just one cup of raw kale provides:
Calories – 33.5
Protein – 2.2 grams
Fiber – 1.3 grams
Vitamin K – 547 mcg (684% of RDV)
Vitamin A – 10,302 IU (206% of RDV)
Vitamin C – 80.4 mg (134% of RDV)
Manganese – 0.5 mg (26% of RDV)
Copper – 0.2 mg (10% of RDV)
Vitamin B6 – 0.2 mg (9% of RDV)
Calcium – 90.5 mg (9% of RDV)
Potassium – 299 mg (9% of RDV)
Iron – 1.1 mg (6% of RDV)
Magnesium – 22.8 mg (6% of RDV)
Thiamine – 0.1 mg (5% of RDV)
Riboflavin – 0.1 mg (5% of RDV)
Folate – 194 mcg (5% of RDV)
2. Kale Has a Big Impact on Eyesight
The high levels of lutein found in kale has made it one of the top foods for eye health. Lutein protects the eyes from damage caused by the sun’s rays, as well as by oxidative stress. Studies have shown that when people increase the amount of kale that they eat to just a half-cup serving per week, they had a decreased risk of developing glaucoma. Additionally, kale’s lutein and beta carotene have been shown to protect against the risk of cataracts and macular degeneration. Eating kale deposits these antioxidants directly into the eye’s retina, where it filters out harmful wavelengths of light.
Bottom Line: By adding a small amount of kale to your weekly diet you can provide yourself with outstanding vision protection.
3. Kale Fights Cancer
There are a lot of foods that lay claim to being cancer killers, but kale is one that has the most studies to back up those claims. Seventy percent of all the research that has looked at cruciferous vegetables have confirmed its protective actions against cancer, and they all point to the same reason: the glucosinolates that are found in their cells. Glucosinolates are chemicals that break down into compounds called indoles and isothiocyanates when kale is chewed and digested. Once this happens they act in a number of different ways. They provide protections against molecular damage to cells and cause cancer cells to die. They also keep blood vessels from forming to feed tumors and stop tumor cells from traveling throughout the body.
Bottom Line: Kale acts against cancer in three different ways. It provides antioxidants that protect against oxidative stress. It provides anti-inflammatories that fight inflammation that can lead to disease. And it provides nutrients that specifically attack cancer cells.
4. Kale Is a Perfect Prenatal Food that Provides Valuable Nutrients for Brain Development During Pregnancy
During pregnancy, women need to focus on nutrition, and one of the most important nutrients that they can eat is folate. It is a vital contributor to brain development. Kale provides 5% of the RDV of kale naturally, which is better absorbed than folic acid from supplements. Adequate amounts of folate lead to healthy formation of the neural tube, healthy birth weights, and lower risk of anomalies in the heart and face. Kale also contains plenty of fiber to keep moms regular, calcium to help build healthy bones, and vitamins A and C to help fight off colds and viruses. Plus, the Vitamin K in kale helps keep blood vessels strong, supporting circulation to the uterus.
Bottom Line: Kale is a healthy way to provide essential nutrition to a growing baby, as well as to support a pregnant woman’s health.
5. Kale is a Heart Healthy Food that Lowers Cholesterol
One of the biggest contributors to heart disease is plaque forming in arteries and clogging them. Plaque is a result of a few different processes, including the inflammation and damage done by free radicals as well as high levels of LDL cholesterol. Kale provides both antioxidants and anti-inflammatory nutrients that lower the risk of this happening. The compounds in kale have been found to minimize oxidative damage while at the same time binding to the bile acids that carry cholesterol. They carry the bad cholesterol out of the body, lowering overall LDL levels. Studies have shown that kale’s biggest cardiovascular impact is derived when it is lightly steamed rather than eaten raw, though both raw and steamed kale are beneficial.
Bottom Line: Kale is the perfect food for heart health. Its nutrients act to minimize the most damaging health conditions that contribute to cardiovascular disease and raise the risk of heart attack.
Tips for Buying, Storing and Cooking Kale
Kale is a cold-weather vegetable, though it is available all year round. When shopping for kale, look for bunches that have smaller leaves, as these will more tender. Kale should always be kept cool, as this will help to keep its leaves fresh. Once you’ve brought it home, do not wash it, as touching water starts a process of breaking down the leaves. Instead, wrap the leaves in paper towels and then store in a plastic storage container, with as little air in the container as possible. Once you’re ready to eat it, rinse the leaves under cold water and chop into slices. The stems are audible, but should be cut smaller than the leaves.
Kale can be eaten raw, which preserves its nutrients. It makes an excellent addition to smoothies and salads. Nutrients are also preserved if they are quickly steamed.