Is spinach or kale better in smoothies?

Smoothies have become an increasingly popular way to get more fruits and vegetables into your diet. Blending leafy greens like spinach and kale into smoothies is a great way to pack a nutritional punch. But which is better for smoothies – spinach or kale?

Nutritional Value

Both spinach and kale are extremely nutritious and counted among the superfoods. They are packed with vitamins, minerals, antioxidants and fiber. Let’s compare the nutritional values of raw spinach and kale:

Nutrient	Spinach	Kale
Calories	7	9
Protein	0.9g	0.9g
Carbs	1g	1.3g
Fiber	0.7g	0.6g
Vitamin A	56% DV	31% DV
Vitamin C	14% DV	41% DV
Vitamin K	145% DV	164% DV
Iron	2% DV	2% DV
Calcium	3% DV	5% DV

As you can see, both spinach and kale provide significant amounts of vitamins A, C and K. They are also great sources of calcium and iron. Kale contains more vitamin C than spinach. Spinach has more vitamin A, but kale contains a decent amount as well. Overall, the nutritional profiles of spinach and kale are quite similar.

Vitamins and Minerals

Here is a more detailed look at some of the key vitamins and minerals found in spinach and kale:

Vitamin A

Spinach contains lutein and zeaxanthin, two carotenoids that the body converts into vitamin A. Just 1 cup of raw spinach provides over 50% of the recommended daily amount of vitamin A. Vitamin A is vital for eye health and acts as an antioxidant to protect cells from damage.

Kale contains decent amounts of carotenoids as well, providing over 30% of the recommended intake of vitamin A in 1 cup. However, spinach is a better source of this important vitamin.

Vitamin C

1 cup of kale provides more than 40% of the recommended daily vitamin C, while spinach contains about 14%. Vitamin C boosts the immune system and acts as a powerful antioxidant in the body.

Kale beats out spinach when it comes to vitamin C content. Add some citrus fruit like oranges to your spinach smoothie to increase the vitamin C content.

Vitamin K

Both spinach and kale excel when it comes to vitamin K, providing over 100% of the recommended daily value in just 1 cup. Vitamin K facilitates proper blood clotting and supports bone health.

Spinach and kale have similar levels of this nutrient. You’ll get all the vitamin K you need for the day from either vegetable.

Iron

Iron is essential for transporting oxygen in the blood. Spinach and kale provide about 2% of the daily recommended amount of iron per cup. Pair them with vitamin C sources like citrus to increase iron absorption.

Overall, spinach and kale are comparable when it comes to vitamins and mineral content. Both provide optimal amounts of vitamins A, C, K and minerals like iron and calcium.

Antioxidants

Antioxidants protect your cells against free radical damage that can lead to disease. Spinach and kale contain similar antioxidant compounds, including quercetin, kaempferol and lutein. These antioxidants reduce inflammation and oxidative stress in the body.

One study found that phytochemicals extracted from spinach effectively inhibited the growth of human cancer cells. The antioxidants in kale have also been shown to prevent cancer and lower cholesterol in some studies.

Both spinach and kale are considered antioxidant powerhouses that can boost your health and protect cells when consumed regularly.

Fiber

Fiber keeps you feeling full, improves digestive health and regulates blood sugar levels. Spinach and kale provide similar amounts of fiber per cup. Spinach has 0.7 grams of fiber while kale contains 0.6 grams.

The green leafy texture of spinach and kale means that they retain their fiber content even when blended. Adding them to smoothies is an easy way to increase your daily fiber intake.

Benefits for Weight Loss

Spinach and kale can both promote weight loss in different ways. Spinach is very low in calories – one cup contains just 7 calories! It provides bulk and satiety without weighing you down.

Kale contains 9 calories per cup. While slightly higher in calories than spinach, kale is still an extremely low-calorie food. It can help fill you up and control hunger.

Both spinach and kale are high volume, low calorie foods. Adding them to smoothies helps create thicker, more satisfying drinks without adding lots of calories.

Nutrient Absorption

The nutrients in spinach are generally more bioavailable than kale. This means the nutrients can be absorbed and utilized easier by the body.

The oxalic acid content of a vegetable can impact how well nutrients are absorbed. Kale contains more oxalic acid than spinach, which may bind to some minerals and reduce absorption. Blanching helps reduce oxalates in kale.

Vitamin C improves the absorption of iron from plant-based foods. Adding a squeeze of lemon to your kale smoothie can increase iron absorbed from the kale itself.

Taste and Texture

Kale has a more assertive, earthy flavor compared to spinach’s milder taste. Some find raw kale to have a tough, fibrous texture.

Spinach has a more delicate flavor that blends smoothly. Spinach has less of the bitterness that can come from kale’s compounds like glucosinolates and isothiocyanates.

Blending kale into smoothies breaks down its fibers for a creamy texture. Still, spinach tends to blend a little smoother. Combining the two creates great flavor and texture.

Potential Downsides

Spinach and kale do contain compounds that impact thyroid function when eaten raw in very large amounts over a long period of time. Cooking neutralizes these antinutrients.

Oxalates may be a concern for those prone to kidney stones. Kale has more oxalates than spinach, but blending and cooking help reduce oxalate content.

The Verdict

Spinach and kale are extremely healthy ingredients that both have benefits in smoothies. While their nutrient profiles are fairly comparable, there are some key differences.

Spinach contains more vitamin A and has a higher bioavailability of nutrients. It has a milder taste and smoother texture. However, kale provides more vitamin C. It also has a bolder, more interesting flavor.

The best approach may be to combine these two superfoods in your smoothies. Try using one cup each of spinach and kale. This gives you the vitamin A of spinach and the vitamin C boost from kale. It also allows you to enjoy the flavors and textures of both.

Aim for organic produce when possible to minimize pesticide exposure. Store greens properly in the refrigerator to retain nutrients. Consider blanching kale before adding to smoothies to reduce compounds that impact thyroid function and nutrient absorption.

Drink spinach and kale smoothies as part of a healthy diet rich in fruits, vegetables, lean proteins and whole grains. Pair it with an active lifestyle for the best health and weight loss benefits.

Both spinach and kale can be stellar ingredients in smoothies. The combination provides a powerhouse of nutrition to promote your health!