Kale vs. Spinach: Which Is More Nutritious?

Leafy greens are among the healthiest foods on the planet, offering benefits for heart health, brain health, and blood sugar control.123 While there’s a great debate over whether spinach or kale is healthier, both are packed with nutrients and plant compounds that benefit your health. This doesn’t mean they’re the same, though.
In this article, we will examine the nutritional differences between spinach and kale and how they compare in their taste and uses in recipes.
Nutritionally, How Does Kale vs. Spinach Compare?
We often hear kale referred to as a “superfood” because of all its nutrients, but the truth is that it’s not necessarily any more special or more nutritious than other leafy greens. For instance, spinach and kale are powerhouse leafy greens rich in various nutrients.

Superfoods

“Superfood” is a marketing term used to describe nutrient-dense foods that offer health benefits.

Fiber

Plant foods like leafy greens are the only source of dietary fiber. Fiber is an essential nutrient for feeding your gut microbiome, or the community of good bacteria that live there.5 It helps support your digestive, heart, and immune health and encourages healthy blood sugar regulation.67
Surveys have found that most Americans don’t get enough fiber, with an estimated 95% of adults not consuming the minimum recommended daily amount, around 30 grams.11 Adding spinach and kale to your diet is a great way to help boost fiber intake.

Vitamin K

Vitamin K is an important nutrient for blood clotting or slowing blood flow when you have an injury so that the wound can heal. It also plays a role in supporting bone health along with calcium and vitamin D.1213
Leafy greens like spinach and kale contain vitamin K1, whereas certain animal products and fermented foods provide vitamin K2.14

Vitamin C

Vitamin C is a water-soluble vitamin and antioxidant which helps protect cells from damage and supports immune health.16 While it’s often attributed to citrus fruits like oranges, vitamin C can also be found in leafy greens.

Vitamin A

Getting enough vitamin A, specifically 3,000 international units daily, is important for immune function and eye health.1715 Spinach and kale contain compounds called “carotenoids,” which our bodies convert to a usable form of vitamin A.18

Calcium

You may think of dairy products when you see the word “calcium,” but plenty of plant foods, including spinach and kale, also provide calcium. Adequate calcium consumption supports healthy bones and teeth, nerve communication, and muscle movement.19

Folate

Folate is a B vitamin best known for its importance in pregnancy to help prevent neural tube defects, like spina bifida, in fetuses.
What About Kale vs. Spinach in Raw vs. Cooked Form?
If you’ve ever cooked leafy greens, you know how much they shrink from their raw form. A whole box of raw spinach can quickly become a small pile of cooked spinach as it shrinks. But how does cooking affect leafy greens nutritionally?

The primary difference is that you can consume more spinach or kale in their cooked versus raw form simply because there is less volume. This also means you’ll get more nutrients per serving in cooked versus raw leafy greens.
However, some water-soluble vitamins can be lost when spinach or kale are cooked using water-heavy methods, such as boiling, or when they come into contact with oil, like sauteing. Research has found that steaming, baking, and microwaving preserve nutrients, antioxidants, and other beneficial plant compounds more than other vegetable cooking methods.232324