Kale has become one of the most popular superfoods in recent years. This dark, leafy green is packed with vitamins, minerals, and powerful plant compounds. Drinking kale juice is an easy way to reap many of its benefits. This article takes an in-depth look at kale juice and its health effects.
Kale is highly nutritious and provides large amounts of vitamins, minerals, and antioxidants in very few calories. One cup (67 grams) of raw kale contains (1):
- Calories: 33
- Protein: 2.5 grams
- Carbs: 6 grams
- Fiber: 2.4 grams
- Vitamin A: 206% of the RDI
- Vitamin C: 134% of the RDI
- Vitamin K: 684% of the RDI
- Vitamin B6: 9% of the RDI
- Manganese: 26% of the RDI
- Calcium: 9% of the RDI
- Copper: 10% of the RDI
- Potassium: 9% of the RDI
- Magnesium: 6% of the RDI
Kale is especially high in vitamins A, C, and K. It also contains small amounts of B vitamins, calcium, potassium, magnesium, and manganese.
Benefits of Kale Juice
Drinking kale juice is an excellent way to increase your nutrient intake. Here are some of the main benefits of kale juice:
Excellent Source of Antioxidants
Kale is packed with antioxidants like quercetin, kaempferol, vitamin C, and various carotenoids. These help fight inflammation and protect cells from damage by unstable molecules called free radicals (2, 3, 4).
May Lower Cholesterol
Kale contains bile acid sequestrants, which help lower cholesterol levels. Drinking kale juice regularly may help reduce LDL (bad) cholesterol levels by up to 10–15% (5).
Rich in Vitamin K
Just 1 cup (67 grams) of kale contains over 680% of the RDI for vitamin K. Vitamin K plays a major role in blood clotting and bone metabolism (6).
High in Vitamin C
Kale provides over 100% of the RDI for vitamin C per cup (67 grams). Vitamin C helps support immune function and is important for skin health and iron absorption (7).
Contains Compounds That May Protect Against Cancer
Kale contains indole and isothiocyanate compounds, which have been studied for their anti-cancer effects (8).
However, more human studies are needed to determine kale’s exact effects on cancer.
Rich Source of Vitamin A
Just 1 cup (67 grams) of kale contains over 200% of the RDI for vitamin A in the form of provitamin A carotenoids like beta-carotene. Vitamin A supports eye health and is important for immune function (9).
May Lower Blood Sugar Levels
In an 8-week study in 24 people with type 2 diabetes, drinking 16 ounces (480 ml) of kale juice daily significantly reduced blood sugar levels and improved liver and kidney function (10).
May Support Heart Health
The fiber, vitamin K, potassium, and antioxidants in kale juice may support heart health. However, human studies are needed (11, 12).
Downsides of Kale Juice
While nutritious, drinking kale juice regularly may have some downsides:
Kale contains moderate amounts of oxalates, compounds that can bind to minerals like calcium and iron in your gut, preventing absorption. People prone to kidney stones may want to limit kale juice (13).
High in Vitamin K
Kale is very high in vitamin K. Those taking blood thinners should keep intake consistent to reduce risks of excessive bleeding or blood clots (14).
Juicing kale removes its fibrous content, an important nutrient that supports gut and heart health (15). Try blending rather than juicing to retain the fiber.
May Cause Thyroid Problems When Consumed in Excess
Very high intakes of kale have been associated with thyroid issues in animal studies due to its high goitrogen content (16).
However, this is unlikely to affect humans consuming normal amounts of kale juice. Those with thyroid issues should moderate intake and cook kale to reduce goitrogens.
Oxidizes and Goes Bad Quickly
Like most fresh juices, kale juice oxidizes and loses nutrients quickly after juicing. Drink immediately or store in an airtight container for up to 24 hours.
There are currently no official guidelines for how much kale juice to drink each day.
Most studies showing benefits used between 8 and 16 ounces (240–480 ml) per day.
It’s best to start with a small amount like 4–8 ounces (120–240 ml) and gradually work your way up to assess your tolerance.
As a general rule, aim to get 2–3 servings of vegetables in juice or other forms at each meal. Overdoing any one source is unwise.
Kale vs. Spinach
Kale and spinach are both extremely nutritious greens. The table below compares the nutrients in 1 raw cup (67 grams) of each (1, 17):
|Protein||2.5 grams||1 gram|
|Carbs||6 grams||1 gram|
|Fiber||2.4 grams||0.7 grams|
|Vitamin A||206% DV||56% DV|
|Vitamin C||134% DV||15% DV|
|Vitamin K||684% DV||166% DV|
|Manganese||26% DV||20% DV|
As you can see, kale contains more protein, carbs, fiber, vitamin C, and vitamin K than spinach. Spinach contains more vitamin A, but kale is still an excellent source.
Overall, both make excellent additions to juice and provide a range of important nutrients. Combining the two is an easy way to make your juice even more nutritious.
Kale Juice vs. Smoothies
Both kale juice and smoothies are great ways to increase your kale intake. However, there are some differences between the two:
|Kale Juice||Kale Smoothie|
|Contains no fiber since juice extracts the liquid and leaves the fiber behind||Retains all the fiber since the blender pulverizes the kale leaves|
|Absorbs more quickly into your bloodstream||Slower to digest due to fiber content|
|Less filling||More satiating due to fiber and use of milk or yogurt|
|Slightly more vitamin C but fewer fat-soluble vitamins like A and K that need fat for absorption||Higher in vitamins A and K since blender helps break down plant cell walls to free these vitamins|
|Goes bad more quickly||Lasts longer in the fridge|
Smoothies are more filling and retain fiber, while juice may be preferable when you want a quick burst of nutrients. Combining the two makes a balanced approach.
How to Make Kale Juice
It’s easy to make green juice using a blender, food processor, or juicer. Follow this simple kale juice recipe:
– 5 kale leaves
– 2 cucumbers
– 2 celery stalks
– 1 lemon, peeled
– 2.5 cups water
– Ice cubes
1. Wash produce thoroughly.
2. If using a blender, juice the lemon and add to the blender along with the kale leaves, cucumber, celery, water, and several ice cubes. Blend on high until smooth.
3. If using a juicer, feed ingredients through the juicer one by one, alternating with water.
4. Pour into a glass and drink immediately or store in an airtight container.
You can also try adding fruits like apple, berries, mango, or pineapple for flavor. Ginger, turmeric, and mint also make tasty additions.
Kale juice packs a nutritional punch, providing antioxidants, vitamins, minerals, and plant compounds that support health. It may help lower cholesterol and blood sugar levels while supporting eye, bone, heart, and immune system health.
However, kale juice lacks fiber and some nutrients compared to whole kale. For best results, try alternating between kale smoothies and green juice while also eating whole vegetables.
Overall, kale juice is a healthy addition to a balanced diet when consumed in reasonable amounts. Add this vibrant green juice to your routine to boost nutrition and experience the many benefits of kale.