Which leafy green has the most fiber?

December 1, 2025 •

4 min read

According to nutrition data, a cup of cooked collard greens is among the top contenders for fiber content. However, several other leafy greens also pack a significant fibrous punch, offering numerous health benefits for digestion, cholesterol, and overall wellness.

Quick Summary

This article explores the fiber content of various leafy greens, highlighting the top performers for boosting dietary fiber. It covers the health benefits of a high-fiber diet and provides practical tips for integrating these nutrient-dense vegetables into daily meals.

Key Points

Top Fiber Leader: Cooked collard greens and turnip greens often contain the most fiber per cup, exceeding other popular options like raw spinach.
Cooking Concentrates Fiber: Sautéing or boiling leafy greens like spinach and kale reduces their volume, significantly increasing their fiber concentration per serving.
Mix and Match for Variety: A blend of greens, such as romaine, kale, and spinach, provides a diverse range of nutrients and textures for salads and other meals.
High-Fiber Diet Benefits: Adequate fiber intake promotes healthy digestion, lowers cholesterol, stabilizes blood sugar, and aids in weight management.
Versatile Cooking Methods: Fibrous greens can be easily added to smoothies, soups, stews, and side dishes to boost your daily fiber intake effortlessly.

Fiber-Rich Leafy Greens: Top Contenders

While many people assume spinach is the fiber king, several other leafy greens offer comparable or even higher amounts, especially when cooked. Cooking reduces the volume of the leaves, concentrating the fiber and nutrients into a smaller portion. The undisputed leaders often include collard greens, turnip greens, and mustard greens.

The Heavyweights: Collards and Turnip Greens

For most people in the Western diet, the top spot is a tie between cooked collard greens and turnip greens. These robust greens offer a substantial amount of fiber per serving. A single cup of cooked collard greens can provide around 5.5 grams of fiber, while cooked turnip greens offer a similar amount at 5 grams. This makes them excellent choices for those looking to significantly increase their fiber intake without consuming excessive volume. Beyond fiber, these greens are loaded with vitamins A, C, and K, as well as calcium and iron.

Other Excellent Fiber Sources

While the top spots are competitive, other greens also deserve recognition for their fiber content and health benefits:

Swiss Chard: A cup of cooked Swiss chard delivers approximately 3.7 grams of fiber, along with a rich supply of vitamins and minerals. Its mildly sweet flavor and colorful stalks make it a versatile addition to many dishes.
Spinach: Cooked spinach contains about 4 grams of fiber per cup, a significant boost compared to its raw form. This powerhouse is also rich in iron, calcium, and antioxidants, supporting bone and immune health.
Kale: This popular superfood provides around 3 to 6 grams of fiber per cup when cooked, depending on the variety and preparation. Known for its high vitamin K and antioxidant content, kale is a solid choice for a fiber-rich diet.
Romaine Lettuce: While not as fiber-dense as cooked greens, a cup of romaine offers about 2 grams of fiber, making it a better choice than iceberg for salad bases.

The Health Benefits of Dietary Fiber

Eating a high-fiber diet is crucial for maintaining optimal health. Fiber, which is the indigestible part of plant-based foods, supports the body in numerous ways.

Digestive Health: Insoluble fiber adds bulk to stool, promoting regular bowel movements and preventing constipation. Soluble fiber, on the other hand, forms a gel-like substance that can soften stool and regulate blood sugar.
Heart Health: Soluble fiber helps lower cholesterol levels by binding to cholesterol particles in the digestive system and removing them from the body before they can be absorbed.
Weight Management: Fiber-rich foods tend to be more filling and require more chewing, which helps control appetite and reduce overall calorie intake.
Blood Sugar Control: By slowing the absorption of sugar, soluble fiber can help stabilize blood sugar levels, which is particularly beneficial for managing type 2 diabetes.

Comparison Table of Common Leafy Greens (Cooked, per 1 cup)


Leafy Green	Fiber Content (approx. grams)	Best For	Nutritional Highlights
Collard Greens	5.5	Stews, braises, side dishes	Vitamins A, C, K; Calcium; Iron
Turnip Greens	5	Sautéing, soups	Vitamins A, C, K; Calcium
Swiss Chard	3.7	Sautéing, stir-fries, quiches	Vitamins A, C, K; Magnesium
Spinach	4.3	Soups, smoothies, pastas, sauces	Iron; Vitamins A, K; Antioxidants
Kale	3–6	Salads (massaged), chips, smoothies	Vitamins K, C, A; Antioxidants

How to Increase Your Leafy Green Fiber Intake

Incorporating more fibrous greens into your diet can be delicious and straightforward. Here are some ideas:

Bulk up smoothies: Add a handful of spinach or kale to your morning smoothie. The taste is easily masked by fruit and other ingredients.
Build better salads: Use a mix of fibrous greens like romaine and kale for a crunchier, more satisfying base. Top with other high-fiber veggies like carrots or bell peppers.
Sauté side dishes: Quickly sauté cooked collards, turnip greens, or chard with garlic and olive oil for a simple, nutrient-dense side dish.
Fortify soups and stews: Stir in a generous amount of chopped spinach or kale toward the end of the cooking process. The greens will wilt down perfectly.
Make wraps: Use large, sturdy leaves like collards as a low-carb, high-fiber alternative to tortillas for wraps.

Conclusion: Choosing Your Fiber-Rich Champion

While several leafy greens contribute significantly to your daily fiber intake, cooked collard greens and turnip greens typically lead the pack. However, the 'best' green is ultimately the one you enjoy eating most consistently. Incorporating a variety of these nutrient-dense options ensures a broad spectrum of vitamins, minerals, and both soluble and insoluble fiber. By making conscious choices to include these fibrous vegetables, you can actively support your digestive system, heart health, and weight management goals. The real takeaway is that cooking your greens is an easy way to increase fiber per serving, and there is a powerful option for every dish.

Here is a useful guide from the National Institutes of Health regarding dietary fiber recommendations.

Frequently Asked Questions

Cooking greens, such as boiling or sautéing them, does not destroy the fiber. Instead, it reduces the overall volume of the vegetable, which concentrates the fiber into a smaller, more manageable portion, making it easier to consume more per serving.

Cooked spinach contains a higher fiber concentration per cup than raw spinach. While a cup of raw spinach contains about 0.7 grams of fiber, a cup of cooked spinach packs around 4 grams due to the volume reduction.

Many vegetables are excellent sources of fiber. Some notable examples include artichokes, Brussels sprouts, broccoli, and sweet potatoes. Legumes and whole grains also provide substantial amounts of dietary fiber.

Health organizations, such as the American Heart Association, generally recommend that adults consume at least 25–30 grams of fiber per day from food. However, specific needs can vary based on age, gender, and individual health factors.

While leafy greens are a fantastic source of fiber, it's best to get your fiber from a variety of sources. Incorporating fruits, legumes, whole grains, nuts, and seeds will ensure you consume a full spectrum of both soluble and insoluble fiber for optimal health.

Soluble fiber dissolves in water and forms a gel, helping to lower cholesterol and control blood sugar. Insoluble fiber does not dissolve and adds bulk to stool, promoting regular bowel movements. Leafy greens contain a mix of both.

Yes, freezing does not typically diminish the fiber content of vegetables. Frozen spinach, for example, is just as fibrous and nutritious as fresh spinach, making it a convenient and cost-effective option.