5 Health Benefits of Kale

A person holding a bunch of kale

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Kale is a leafy green vegetable with a lot of versatility and a strong nutritional composition full of vitamins A, C, and K, fiber and antioxidants. Kale belongs to the cabbage family, along with Brussel sprouts, broccoli, and other cruciferous vegetables. You can identify kale it by its green or purple curly leaves.

Kale has been used since before the Middle Ages throughout Europe, Asia, South America, and Africa, but it took much longer for it to be made popular in U.S. diet. Today, most of the kale grown in the U.S. comes from farms in California farms, Georgia, New Jersey, and Texas.

Keep reading to learn how adding kale to your diet can benefit your health, and how to go about consuming it regularly.

May Reduce Macular Degeneration Risk

Kale is a natural source of a natural plant compound called carotenoids. One carotenoids, called lutein, may help protect the eyes from developing a condition called macular degeneration. Having macular degeneration means you lose vision in the center of your field of vision. 

Some data shows that the concentrations of lutein in plasma and the macular pigment increased significantly after consuming kale extract every day for four weeks. Other data shows higher plasma lutein was associated with a 37% reduced risk of macular degeneration. Therefore, adding kale to your diet can have a positive impact in your eye health, reducing the risk of a condition such as macular degeneration.

May Support Heart Health

Heart disease is the number one killer of both male and female adults in the U.S Including kale in your diet may protect the health of your heart, especially if it is included in an overall heart-healthy diet. 

One study evaluated how supplementing with kale juice affected the risk of coronary artery disease among 32 men with high cholesterol. The participants consumed 150 milliliters (mL) of kale juice per day for a 12-week intervention period.

The researchers of the study concluded that supplementing with kale juice regularly could have a positive impact on blood cholesterol levels. Some evidence suggests the intake of a compound naturally found in kale, called sulforaphane, may have effects that can help reduce the risk of cardiovascular disease.

May Reduce The Risk Of Certain Cancers

The risk of developing cancer can be impacted by many factors, including some that are completely out of your control, like genetic predispositions. While eating kale won’t necessarily be the magic bullet to living a cancer-free life, adding it your diet may help reduce the risk of certain cancers. However, more studies are needed to confirm this. 

That said, some studies have that that the sulforaphane compound found in kale may have inhibitory effects on breast cancer, lung cancer, liver cancer, and other malignant tumors. So, while stronger data is needed to confirm this link, the evidence suggesting that kale may protect against certain cancers is promising.

May Support Bone Health

When it comes to nutrients that support your bone health, calcium tends to be the most popular and well-known. While it's true that calcium can have an important role in promoting good bone health, it isn’t the only nutrient that has an impact on the strength of your bones.

Like most leafy greens, kale is a great source of vitamin K, which has an important role in bone health. Some data suggests that vitamin K deficiency has been associated with a higher risk of bone fractures. One cup of cooked kale provides 493 micrograms (mcg), far more than the recommended "adequate intake" for this nutrient for healthy adults.

May Support Gut Health

Having a healthy and balanced gut microbiota means that your gut is home to a diverse range of microorganisms working together in harmony to support your health in various ways. Kale may help support a healthy and balanced gut microbiota. 

The high proportion of soluble and insoluble fiber, as well as certain plant compounds, found in kale may positively affect the balance and quantity of the live bacteria found in your gut (probiotics). One study using mice showed that, among those who were obese and didn’t have a healthy and balanced gut microbiome, those which consumed kale showed positive effects on its gut microbiome. That said, additional studies on humans are needed to draw conclusive statements.

Kale Nutritional Facts 

Here are the nutrition facts of one cup of raw kale, according to the USDA:

  • Calories: 7
  • Carbs: 1 g
  • Fiber: 1 g
  • Vitamin K: 493 micrograms (mcg), 68% of the Daily Value (DV)
  • Vitamin C: 21 milligrams (mg), 22% of the DV
  • Manganese: 0.64 mg, 8% of the DV
  • Vitamin A: 172 mcg 6% of the DV
  • Riboflavin: 0.17 mcg, 5% of the DV
  • Calcium: 177 mg, 4% of the DV

Kale also contains smaller quantities of many other nutrients, including folate. It is also a source of plant compounds that may support your health in various ways. 

Risks of Eating Kale 

While kale is highly nutritious and a great addition to most diets, it's also important to mention that overconsuming kale can lead to a few potential risks. Kale contains substances called thallium and goitrogens. Thallium is a heavy metal that can be harmful to humans in large amounts, and goitrogens can interfere with thyroid function if eaten in excessive quantities.

Kale is also a source of oxalic acid, a compound that may negatively impact your body’s ability to absorb calcium. Some evidence suggests soaking and heating of high oxalate food, like kale, may help reduce the oxalate content.

Additionally, kale is high in Vitamin K, which can interfere with blood thinners such as warfarin. Therefore, those taking such medication should monitor their intake of kale and other leafy greens. Lastly, due to its high fiber content, overconsuming kale can lead to bloating, gas, and other digestive issues. It's always recommended to maintain a varied diet to ensure a balanced intake of different nutrients.

Tips For Consuming Kale 

Incorporating kale into your diet can be a simple and flavorful endeavor. One of the most straightforward ways is to add raw kale to your salads. The leafy green adds a robust texture and a slightly bitter flavor that can be balanced with sweet fruits like apples or pears.

For a warm option, you can saute kale in a bit of olive oil and garlic, and then serve it as a side dish. Kale chips are a popular, crunchy alternative to potato chips and are easy to make at home with just a little bit of olive oil and seasoning.

For those who enjoy a morning smoothie, adding a handful of kale can significantly boost its nutritional value. 

A Quick Review

There are numerous health benefits associated with incorporating kale into your diet. Kale is packed with nutrients that support our health in various ways, and it can be added to dishes with very little effort. 

However, as with all foods, it's crucial to consume kale as part of a balanced diet. Overconsumption can lead to potential risks such as digestive issues and interference with certain medications. But when consumed adequately, kale can be an excellent addition to an overall balanced and healthy diet.

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10 Sources
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