Green peas top the list at 9 grams of fiber per cooked cup, making them one of the most fiber-dense vegetables you can eat. Behind them, broccoli, turnip greens, and Brussels sprouts each deliver 4.5 to 5 grams per cup. Most adults need between 22 and 34 grams of fiber daily, so choosing the right vegetables can cover a significant chunk of that goal.
The Highest-Fiber Vegetables Per Serving
Here’s how common vegetables rank when measured by a standard serving size:
- Green peas (1 cup, boiled): 9 grams
- Broccoli (1 cup chopped, boiled): 5 grams
- Turnip greens (1 cup, boiled): 5 grams
- Brussels sprouts (1 cup, boiled): 4.5 grams
- Potato with skin (1 medium, baked): 4 grams
- Sweet corn (1 cup, boiled): 4 grams
- Cauliflower (1 cup chopped, raw): 2 grams
- Carrot (1 medium, raw): 1.5 grams
Green peas stand out dramatically. A single cup gets you roughly a third of the way to the daily target for most adults. Broccoli and turnip greens tie for second, and both are low in calories, giving you a lot of fiber per bite.
Root Vegetables Worth Adding
Root vegetables often get overlooked as fiber sources, but several pack a solid punch. Per 100 grams (a little under a cup for most), cooked taro provides 5.1 grams of fiber. Raw parsnips come in at 4.9 grams per 100 grams, though that drops to about 3.6 grams once boiled. Jicama matches raw parsnips at 4.9 grams per 100 grams, and its crunchy texture makes it easy to eat raw in salads or with dips.
Sweet potatoes baked in their skin deliver about 3.3 grams per 100 grams. Yams are slightly higher at around 4 grams per 100 grams when cooked. Raw beets contain 2.8 grams per 100 grams, but cooking drops that to 2 grams. If you’re choosing between root vegetables for fiber alone, parsnips, taro, and jicama give you the most.
Don’t Peel Your Potatoes
Up to 31% of a vegetable’s total fiber sits in the skin. That’s a meaningful amount, especially for potatoes and sweet potatoes. A baked potato eaten with its skin provides 4 grams of fiber; peel it, and you lose over a gram. The same principle applies to carrots and beets. If the skin is edible and you can tolerate the texture, leave it on.
Cruciferous Vegetables Compared
Broccoli, cauliflower, and Brussels sprouts all belong to the cruciferous family, but their fiber content isn’t identical. Raw Brussels sprouts contain 3.3 grams per cup, raw broccoli has 2.4 grams, and raw cauliflower trails slightly at 2.1 grams. Cooking concentrates these vegetables (the cup shrinks as they wilt), which is why cooked serving sizes show higher numbers: a cup of boiled Brussels sprouts jumps to 4.5 grams, and boiled broccoli reaches 5 grams.
All three are versatile enough to eat daily, so the best choice is whichever one you’ll actually enjoy eating consistently.
Soluble vs. Insoluble Fiber in Vegetables
Fiber comes in two forms, and most vegetables contain both. Soluble fiber dissolves in water and forms a gel-like material during digestion, which slows things down and helps lower cholesterol and blood sugar. Peas, carrots, and beans are particularly rich in soluble fiber. Insoluble fiber doesn’t dissolve. It adds bulk to stool and helps everything move through your digestive tract more efficiently. Cauliflower, green beans, and potatoes are good sources of insoluble fiber.
You don’t need to track the ratio between the two types. Eating a variety of vegetables naturally gives you both.
How Cooking Affects Fiber
Cooking changes the balance between soluble and insoluble fiber but doesn’t destroy the total amount. Research on cruciferous vegetables found that both boiling and steaming reduced insoluble fiber while increasing soluble fiber. The total fiber content, however, stayed roughly the same. Studies on Brussels sprouts, broccoli, and cauliflower specifically confirmed that steaming did not significantly reduce overall fiber.
This means you can cook your vegetables however you prefer without worrying about losing fiber. Roasted, steamed, or boiled, the fiber is still there. The main reason cooked vegetables sometimes show higher per-cup numbers is simply that they shrink during cooking, so you fit more into a measuring cup.
How Much Fiber You Actually Need
The daily recommendation varies by age and sex. For women, the target is 28 grams at ages 19 to 30, dropping to 25 grams from 31 to 50, and 22 grams after 51. For men, it’s 31 grams at ages 19 to 30, peaks at 34 grams from 31 to 50, and returns to 31 grams after 51. Most people fall well short of these numbers.
Vegetables alone probably won’t get you all the way there, but they form a strong foundation. A cup of green peas, a cup of broccoli, and a baked potato with skin give you 18 grams combined, which is more than half the daily goal for most adults. Whole grains, beans, fruits, and nuts fill in the rest.
Adding Fiber Without Digestive Trouble
If your current fiber intake is low, jumping straight to large servings of peas and Brussels sprouts can cause gas and bloating. Your gut bacteria need time to adjust to a higher fiber load. Increase your intake gradually over two to three weeks, adding one extra serving of high-fiber vegetables every few days. Drinking more water alongside the extra fiber helps it move through your system smoothly, since soluble fiber absorbs water as part of its gel-forming process.
Cooking vegetables rather than eating them raw can also make them easier to digest at first. As your body adapts, you can mix in more raw options like jicama, carrots, and cauliflower without discomfort.