The 11 Vegetables That Pack the Most Fiber Per Serving, According to RDs

If you were to look at a list of the things most health experts can agree on, you’d certainly find the fact that fiber should be a key part of the most people's diets on there. “Fiber plays an important role in overall health and especially digestive health, preventing constipation, and helping maintain stable blood sugars,” says registered dietitian Kaleigh McMordie, MCN, RDN. But that’s not all. McMordie goes on to detail that fiber helps regulate cholesterol, improve heart health, and could even lower your risk of certain cancers, like colon cancer and breast cancer. “Undigested fiber serves as ‘food’ to the beneficial bacteria that live in the large intestine," she says. "As they feed off of the fiber, these bacteria produce nutrients for the body, including various short chain fatty acids that are responsible for a number of fiber's health benefits.”

Unfortunately, most of us aren’t getting enough fiber. “According to the Dietary Guidelines for Americans, 90 percent of women and 97 percent of men in America do not meet the dietary recommendations for fiber,” says registered dietitian Maria Sylvester Terry, MS, RDN, LDN.

So, how much fiber do you need?

The current American Dietary Guidelines recommend the below (with the lower end for adults over 50):

• 31-34 grams per day for men
• 22-28 grams per day for women

The most fiber-rich vegetables

There are innumerable benefits to following a plant-rich diet, but the high fiber found in many plant foods is chief among them. “I always recommend eating naturally fiber-rich foods like vegetables over fiber-added foods, because most vegetables contain a mix of soluble and insoluble fiber, both of which are beneficial,” says McMordie. "Foods that are naturally rich in fiber also often contain a bounty of vitamins, minerals, and powerful antioxidants. Supplements and foods with added fiber usually contain highly processed or synthetic forms of fiber, and many times lack the same benefits that whole food sources offer. They should be considered more of a supplement to fill in the gaps.”

With that in mind, here are the 11 most fiber-rich vegetables (which are one of the best food groups for upping your *natural* fiber intake), according to McMordie.

1. Artichokes: 4.8 g for 1/2 cup artichoke hearts

“Artichokes are very high in fiber, including inulin, which acts as a prebiotic. They also contain a decent amount of protein for a vegetable," McMordie says. "They’re also incredibly versatile: You can add artichokes to salads, blend them into dips, or boil them and eat them as an appetizer.”

2. Peas: 4.1 g per 1/2 cup

“Frozen green peas couldn't be any easier to eat, whether added to salads, soups, or eaten as a simple side dish,” McMordie says.

3. Sweet Potatoes: 3.9 g for one medium potato (about five inches) with skin

According to McMordie, sweet potatoes are a great source of both soluble and insoluble fiber, especially with the skin. "They are also a great source of vitamin A and antioxidants," she adds. "Sweet potatoes can be prepared in so many ways, from baking or roasting, to mashed or even sweet potato ‘toast.’ Be sure to include the skin for the most fiber.”

4. Potatoes: 3.6 g for one medium potato with skin

“Potatoes are loaded with nutrients, like potassium, vitamin C, and B6. They also have resistant starch, which acts as a prebiotic. Be sure to include the skin and stick to healthier cooking methods, like baking or roasting for the most heart health benefits,” says McMordie.

5. Parsnips: 3.3 g per 1/2 cup

“This root veggie is a lesser-known fiber powerhouse. Parsnips are delicious roasted or mashed, similar to potatoes.”

6. Winter squash (acorn or butternut squash): 3.2 g per 1/2 cup cooked

"Winter squash is very high in fiber and it's loaded with vitamin A and antioxidants. When roasted, the skin of acorn squash is edible, adding even more fiber.”

7. Jicama: 2.9 g per 1/2 cup

This crunchy veggie is delicious eaten raw, but can also be cooked. "Jicama is high in vitamin C and antioxidants, and has a high water content and contains inulin, a type of fiber that is great for preventing or relieving constipation,” McMordie says.

8. Mustard Greens: 2.6 g per one cup raw

“Mustard greens—and other tougher leafy greens like turnip greens and collards—are high in fiber, vitamin K, and cancer-fighting antioxidants. Because these greens shrink down so much during cooking, eating them cooked can pack even more nutrients into a single serving.”

9. Corn: 1.8 g per 1/2 cup cooked

According to McMordie, corn is a great source of fiber, and it is so easy and versatile to cook with. "Fresh, sweet corn is delicious raw in salads or grilled on the cob. During winter months, it is readily available frozen or canned,” she adds.

10. Brussels Sprouts: 1.7 g per 1/2 cup

“Like other cruciferous vegetables, Brussels sprouts are high in both fiber and a phytochemical called glucosinolate that could offer protection against certain cancers. They're also a great source of vitamins K and C.”

11. Beets: 1.7 g per 1/2 cup cooked

“Besides being rich in fiber, beets are also high in folate, manganese, and copper. The deep pigments in beets signals high levels of inflammation-fighting antioxidants. Beets are delicious roasted, and you can also find them pickled or canned. As an added bonus, beet greens are high in fiber, too,” says McMordie.

Honorable mentions:

• Asparagus: 1.4 g per 1/2 cup
• Green beans: 1.4 g per 1/2 cup
• Carrots: 1.3 g per 1/2 cup raw
• Broccoli: 1.1 g per 1/2 cup
• Cauliflower: 1.1 g per 1/2 cup
• Cabbage: 1.1 g per 1/2 cup raw

RD notes to keep in mind when eating more fiber-rich vegetables

While fiber can be a glorious addition to your diet (what's not to love about feeling energized and not straining in the restroom?), it should be added slowly, says McMordie. “If your body is not used to a high fiber diet, increasing your fiber intake suddenly could cause gas, bloating, and abdominal pain, so do so slowly,” she says. “And for the most benefit, I recommend getting fiber from a variety of whole food sources, like fruits and vegetables, whole grains, and beans before turning to a supplement.”

You’ll also want to drink plenty of water, since fiber holds onto water. "Drinking eight to 12 cups a day is critical to help flush everything out of your system," says McMordie. Where you fall in the range of water consumption will depend on how many water-rich foods you’re eating (if you’re eating lots of water-rich veggies, you can drink less than if most of your fiber is coming from fiber cereal, for example).