Which Leafy Greens Have the Highest Fiber?

November 23, 2025 •

4 min read

According to data cited in sources like EatingWell, only a small percentage of adults meet the daily recommended fiber intake. To help bridge this nutritional gap, it's essential to know which leafy greens have the highest fiber, offering a simple way to boost your diet with this critical nutrient.

Quick Summary

This guide reveals the top leafy greens for fiber, comparing cooked vs. raw nutritional values and explaining how these fiber-packed vegetables can enhance your health and digestion.

Key Points

Cooked Greens are Fiber-Dense: Cooking leafy greens like collards, turnip greens, and spinach concentrates their fiber, yielding significantly higher amounts per cup than raw versions.
Collard Greens Rank High: Cooked collard greens are one of the most fiber-rich leafy green options, offering up to 6 grams per cooked cup.
Benefit from Soluble and Insoluble Fiber: High-fiber greens provide both types of fiber, which respectively help lower cholesterol and regulate bowel movements for overall digestive health.
Spinach vs. Kale Fiber: When cooked, both spinach and kale provide excellent fiber, but kale often contains slightly more fiber per cup. Raw spinach has much less fiber per cup than raw kale.
Simple Ways to Increase Intake: Easy methods to add more fiber include blending greens into smoothies, stirring them into soups, and using them as a base for wraps or sautéed sides.
Beyond Fiber: Beyond high fiber, these greens offer a wealth of other nutrients like vitamins A, C, K, calcium, and antioxidants, supporting a wide range of bodily functions.

Understanding Fiber in Leafy Greens

Fiber is a non-digestible carbohydrate essential for digestive health, blood sugar control, and feeling full longer. While all leafy greens offer health benefits, their fiber content can vary significantly based on the type and how it's prepared. Cooking greens, for instance, reduces their volume, which can concentrate the fiber per cup measurement compared to their raw state. This is a crucial factor when comparing the fiber content of different greens.

Top Fiber-Rich Leafy Greens

When it comes to raw greens, some options like romaine lettuce offer a solid amount of fiber per cup, while others like arugula contain less. However, cooking can substantially increase the fiber concentration. Here are some of the most fibrous leafy greens, often yielding high fiber counts per cooked cup:

Collard Greens

Cooked collard greens stand out as a top contender, providing an impressive amount of fiber, with reports indicating up to 6 grams per cooked cup. These large, sturdy leaves are rich in vitamins and minerals, including calcium and vitamin K. They are a staple in Southern cuisine and can be simmered or sautéed to create a hearty side dish.

Turnip Greens

Similar to collards, cooked turnip greens are another high-fiber powerhouse, offering around 5 grams per cooked cup. They have a slightly pungent, peppery flavor that mellows with cooking. The tender leaves and stems are both edible and highly nutritious.

Beet Greens

The leafy tops of beets are not only edible but also incredibly nutritious. A cooked cup of beet greens can provide between 4 and 6 grams of fiber, along with antioxidants and other essential nutrients. They have an earthy flavor similar to beets and spinach and can be easily sautéed or added to soups.

Spinach

Spinach is a versatile and popular leafy green, and while its raw fiber content is modest (around 0.7g per raw cup), cooking a larger quantity significantly increases the fiber per cup. A cooked cup of spinach can provide around 4 grams of fiber, in addition to being loaded with vitamins A, C, and K.

Kale

Known for its superfood status, kale offers a substantial fiber boost. One cup of cooked kale contains nearly 5 grams of fiber, providing a combination of soluble and insoluble fiber for digestion and cholesterol management. Raw kale has a lower fiber count per cup but can be massaged to tenderize it for salads.

Swiss Chard

Often referred to as chard, this leafy green is part of the beet family and offers good fiber content. A cooked cup provides approximately 3.7 grams of fiber. Its colorful stalks and tender leaves can be prepared similarly to spinach.

How to Incorporate More High-Fiber Greens

Adding more leafy greens to your diet doesn't have to be a chore. Here are some simple methods:

Smoothies: Add a large handful of spinach or kale to your morning smoothie. The taste is easily masked by fruits like bananas and berries, but you'll get a significant nutrient boost.
Soups and Stews: Stir chopped collard greens, Swiss chard, or spinach into soups and stews during the last few minutes of cooking. They will wilt and blend seamlessly into the dish.
Sautéed Sides: Quickly sauté greens like kale, spinach, or chard with garlic and olive oil for a simple, healthy side dish for any meal.
Sandwiches and Wraps: Use greens like romaine lettuce or spinach as a base for sandwiches and wraps for extra texture and nutrients.
Baked Chips: For a crispy snack, bake kale or turnip greens with a little olive oil and salt until crunchy.

Fiber Content Comparison Table

Here is a comparison of the fiber content of some common leafy greens, measured per cooked cup, based on USDA data.


Leafy Green	Fiber per Cooked Cup (g)	Key Nutrients	Flavor Profile
Collard Greens	~6g	Vitamin K, Calcium, Vitamin A	Hearty, slightly bitter, and earthy
Beet Greens	~6g	Antioxidants, Vitamin K	Earthy, sweet, and similar to spinach
Turnip Greens	~5g	Vitamin C, Iron	Peppery and slightly bitter
Kale	~5g	Vitamin C, Calcium, Lutein	Robust, slightly bitter
Spinach	~4g	Vitamin K, Iron, Folate	Mild and versatile
Swiss Chard	~4g	Magnesium, Potassium	Mild and vegetal

Conclusion: Making the Best Choices

While a definitive answer to "which leafy greens have the highest fiber" points to powerhouse options like cooked collards, turnip greens, and beet greens, the best choice ultimately depends on your personal taste and dietary preferences. By incorporating a variety of these high-fiber greens into your diet through creative cooking methods, you can ensure a well-rounded intake of essential nutrients. A diversified diet of leafy greens will not only boost your fiber but also provide a spectrum of vitamins, minerals, and antioxidants for overall health and well-being. To further explore dietary recommendations, consider referencing the Dietary Guidelines for Americans.

Remember to gradually increase your fiber intake and drink plenty of water to avoid digestive discomfort. With a little creativity in the kitchen, you can make these fibrous greens a delicious and regular part of your meals.

Frequently Asked Questions

A measured cup of cooked leafy greens typically has more fiber than a measured cup of raw greens. This is because cooking shrinks the leaves, concentrating the nutrients and fiber into a smaller volume. For example, a whole bag of raw spinach might cook down to just one cup, resulting in a much higher fiber count per cup.

Per cooked cup, collard greens generally contain more fiber than cooked spinach. Cooked collard greens can have up to 6 grams of fiber per cup, while cooked spinach provides around 4 grams.

You can incorporate high-fiber greens by blending them into smoothies, stirring them into soups or stews, sautéing them as a side dish, or mixing them into pasta sauces. Creating baked kale or turnip green chips is also a great alternative.

Leafy greens contain both soluble and insoluble fiber. Soluble fiber dissolves in water to form a gel, which helps lower cholesterol and control blood sugar. Insoluble fiber adds bulk to stool, aiding digestion and promoting regular bowel movements.

The fiber content can vary slightly depending on the specific variety of kale (e.g., curly kale, lacinato). The preparation method also plays a significant role, as cooking will increase the fiber density per cup compared to raw consumption.

While both are excellent sources, consuming fiber from a variety of sources, including leafy greens, whole grains, fruits, nuts, and legumes, is recommended. A diverse fiber intake supports a more varied and healthier gut microbiome.

Eating high-fiber leafy greens offers numerous health benefits, including improved digestive health, lower cholesterol levels, better blood sugar control, and assistance with weight management due to increased feelings of fullness.