In this article
- Broccoli fiber in the florets and the wider family
- Which broccoli gives the most fiber per calorie?
- How a broccoli serving stacks up against the Daily Value
- What makes broccoli a superfood candidate
- Checking the cancer claim against the research
- Broccoli fiber and your gut
- A stir-fry where riced broccoli changes the count
- A broccoli family shopping checklist
- Fitting broccoli into a full day of fiber
- Where broccoli research goes next
- Broccoli superfood questions
- Sources
Plenty of people buy broccoli because they’ve heard it fights cancer, and its fiber is an afterthought. The research behind that reputation is more mixed than the headlines suggest, while the broccoli fiber story is steady and easy to measure.
Half a cup of boiled broccoli gives you about 2.6 grams of fiber for just 27 calories, according to USDA FoodData Central. That modest serving also covers more than half your daily vitamin C.
This guide looks at broccoli as a superfood from the fiber side, compares it with the broccoli rabe and Chinese broccoli you’ll find in many markets, and checks what the cancer research actually says.
Broccoli fiber in the florets and the wider family
Broccoli shares its shelf with leafy relatives that look and taste different. Broccoli rabe, also sold as rapini, has thin stems, bitter leaves and small buds, while Chinese broccoli, or gai lan, has broad flat leaves and thick stalks.
USDA lists them like this per 100 grams:
| Per 100 g (USDA) | Fiber | Calories | Vitamin C | Vitamin K | Calcium |
|---|---|---|---|---|---|
| Broccoli, raw | 2.6 g | 34 | 89.2 mg | 102 mcg | 47 mg |
| Broccoli, boiled | 3.3 g | 35 | 64.9 mg | 141 mcg | 40 mg |
| Broccoli rabe, cooked | 2.8 g | 25 | 37.0 mg | 256 mcg | 118 mg |
| Chinese broccoli, cooked | 2.5 g | 22 | 28.2 mg | 84.8 mcg | 100 mg |
Boiled broccoli carries the most fiber by weight here. Cooking drives off water and shrinks the florets, so the same 100 grams holds more plant material.
The relatives win on other counts. Cooked broccoli rabe brings almost three times the calcium of boiled broccoli and nearly twice its vitamin K, at fewer calories. Its 256 micrograms of vitamin K per 100 grams is more than double the FDA’s 120 microgram Daily Value.
Which broccoli gives the most fiber per calorie?
Fiber per 100 calories is a fair way to compare foods that are already very light. By that measure, the leafy cousins pull ahead:
- Chinese broccoli, cooked: about 11.4 grams of fiber per 100 calories
- Broccoli rabe, cooked: about 11.2 grams
- Broccoli, boiled: about 9.4 grams
- Broccoli, raw: about 7.6 grams
For comparison, cooked white rice offers about 0.3 grams of fiber per 100 calories. Every member of the broccoli family delivers more than 20 times that.
In practice, you can’t eat 100 calories of broccoli rabe in one sitting without trying hard. That would take about 400 grams of the cooked greens, which is why these vegetables matter more for nutrient density than for calorie control.
How a broccoli serving stacks up against the Daily Value
The FDA sets the Daily Value for fiber at 28 grams. A food needs 2.8 grams per serving, 10% of that figure, to be labeled a good source of fiber.
| Serving (USDA) | Weight | Fiber | % DV | Calories |
|---|---|---|---|---|
| Boiled broccoli, 1/2 cup chopped | 78 g | 2.6 g | 9% | 27 |
| Boiled broccoli, 1 cup chopped | 156 g | 5.1 g | 18% | 55 |
| Chinese broccoli, 1 cup cooked | 88 g | 2.2 g | 8% | 19 |
| Riced broccoli, 3/4 cup (frozen, label) | 85 g | 3 g | 11% | 25 |
| Sprout mix with broccoli sprouts, 1/2 cup (label) | 28 g | 1 g | 4% | 10 |
A half cup of cooked broccoli falls just short of the good source line, so a full cup is the more useful portion if fiber is your goal. That cup covers about a fifth of a 25 gram target.
Sprouts are the lightweight of the group. The sprout mix in USDA’s branded database combines broccoli, clover and mustard sprouts and gives about 1 gram of fiber per half cup, so treat sprouts as a garnish rather than a fiber source.
Not sure what your own target looks like in cups of vegetables? Our fiber calculator turns your age and sex into a personal daily number.
What makes broccoli a superfood candidate
Broccoli belongs to the cruciferous family, which the National Cancer Institute lists alongside kale, cabbage, cauliflower, Brussels sprouts, bok choy, arugula and watercress. These vegetables share a group of sulfur containing compounds called glucosinolates.
Glucosinolates give these vegetables their sharp smell and bitter bite. The NCI explains that they break down during food preparation, chewing and digestion into compounds such as sulforaphane and indole-3-carbinol, the two most often studied for anticancer effects.
The NCI also describes cruciferous vegetables as rich in nutrients, including carotenoids such as beta carotene, lutein and zeaxanthin, vitamins C, E and K, folate and minerals. It calls them a good fiber source too.
So broccoli earns a superfood label on nutrient density alone. A food that brings fiber, several vitamins and a family of well studied plant compounds for about 35 calories per 100 grams is hard to beat on a vegetable shelf.
Checking the cancer claim against the research
Lab and animal studies made cruciferous vegetables famous, but the NCI notes that studies in humans have shown mixed results. The pattern differs by cancer type.
- Prostate: most cohort studies found little or no link, though some case control studies found lower risk with higher intake
- Colorectal: cohort studies generally found no association, with one Dutch study showing lower colon cancer risk in women only
- Lung: most studies found little association, with one U.S. analysis linking more than 5 servings a week to lower risk in women
- Breast: a meta-analysis found no association with breast cancer risk
That’s an honest picture for a food with a big reputation. Broccoli is a nutrient dense vegetable with real fiber, and the specific cancer benefit remains unproven in people.
Broccoli fiber and your gut
Mayo Clinic explains that insoluble fiber helps material move through your digestive system and increases stool bulk, and it lists vegetables among its main sources. Broccoli’s firm stalks and florets fit that description well.
Mayo also links high fiber diets with a lower risk of hemorrhoids and diverticular disease. A daily cup of cooked broccoli is a simple way to add to that kind of eating pattern.
Adding a lot of fiber at once, from broccoli or anything else, can bring gas, bloating and cramping, Mayo Clinic notes. It recommends raising fiber gradually over a few weeks and drinking plenty of water, so start with half cup portions if your gut is sensitive.
If bloating is what keeps you away from vegetables like broccoli, our gut health guides lay out a gentler path to eating more of them.
A stir-fry where riced broccoli changes the count
Picture a weeknight stir-fry of cooked Chinese broccoli, garlic and tofu served over a cup of white rice. The greens bring about 2.2 grams of fiber and the rice adds only 0.6 grams, for a total near 2.8 grams.
Now swap half the rice for 3/4 cup of frozen riced broccoli. The base becomes half a cup of rice plus the riced broccoli, and the fiber in the greens and base climbs to about 5.5 grams, roughly double.
Calories move the other way. The original greens and rice come to about 224 calories, while the half and half version lands near 147, so the bowl gets lighter as the fiber goes up.
A broccoli family shopping checklist
Use this list to pick the right form for the meal you have in mind:
- Heads of broccoli for roasting, steaming and snacking, with the stalks peeled and sliced so nothing goes to waste
- Broccoli rabe when you want the most calcium and vitamin K for the fewest calories
- Chinese broccoli for stir-fries and noodle soups, with about 2.2 grams of fiber per cooked cup
- Frozen riced broccoli to stretch rice, risotto or fried rice with about 3 grams of fiber per 3/4 cup
- Broccoli sprouts as a crunchy topping for sandwiches and salads, knowing they add little fiber
Looking for stir-fries, pastas and grain bowls that use the whole broccoli family? Our recipe eBooks are full of easy, fiber rich dinners.
Fitting broccoli into a full day of fiber
Mayo Clinic’s targets are 25 grams of fiber a day for women and 38 grams for men up to age 50, dropping to 21 and 30 grams after 50. Harvard’s Nutrition Source notes that most Americans get only about 15 grams.
A cup of cooked broccoli covers about 20% of a 25 gram goal. Pair it with a serving of beans, a whole grain and a piece of fruit and the rest of the day falls into place.
Broccoli’s vitamin load makes that cup even more worthwhile. The same 156 grams supplies about 101 milligrams of vitamin C, more than the FDA’s 90 milligram Daily Value, and about 220 micrograms of vitamin K, close to twice that nutrient’s Daily Value. Folate adds about 168 micrograms more.
Where broccoli research goes next
The open question is less about broccoli fiber, which is well measured, and more about how glucosinolates behave once you eat them. The NCI points out that these compounds break down during chewing and digestion, which means preparation and your own gut both shape what you absorb.
Until human studies settle the cancer question, the fiber, vitamin C and vitamin K are reason enough to keep broccoli and its leafy relatives on your plate several times a week.
Broccoli superfood questions
Is broccoli a superfood?
It’s a very nutrient dense vegetable. A cup of boiled broccoli has about 5.1 grams of fiber, more than a day’s vitamin C and only 55 calories, though its cancer fighting reputation is not yet proven in human studies.
Does broccoli rabe have more fiber than broccoli?
Not by weight. USDA lists cooked broccoli rabe at 2.8 grams of fiber per 100 grams versus 3.3 grams for boiled broccoli, but rabe has fewer calories, so it wins on fiber per calorie.
Is riced broccoli a good substitute for rice?
Yes, for fiber. One frozen riced broccoli product has 3 grams of fiber in 3/4 cup for 25 calories, while a full cup of cooked white rice has under 1 gram for about 205 calories.
Do broccoli sprouts have fiber?
Only a little. A sprout mix with broccoli sprouts in USDA’s branded database lists 1 gram of fiber per half cup, so sprouts work better as a topping than a fiber source.
Does broccoli prevent cancer?
The evidence is mixed. The National Cancer Institute reports that human studies of cruciferous vegetables have not shown a consistent link with lower cancer risk, even though lab studies look promising.
What is the fiber in Chinese broccoli?
A cup of cooked Chinese broccoli has about 2.2 grams of fiber for 19 calories, according to USDA. It also brings about 88 milligrams of calcium per cup.
How much broccoli do I need to eat for fiber?
There’s no set amount. A cup of cooked broccoli gives about 5 grams, roughly a fifth of a 25 gram daily target, so it works best as one of several fiber foods in your day.
Sources
- U.S. Department of Agriculture, Agricultural Research Service. “FoodData Central” (Broccoli, raw 170379; Broccoli, boiled 169967; Broccoli raab, raw 170381 and cooked 170382; Broccoli, Chinese, cooked 169392; Riced Broccoli 2398233; Broccoli Sprouts 2429132; Rice, white, long-grain, cooked 168878). 2026. fdc.nal.usda.gov
- National Cancer Institute. “Cruciferous Vegetables and Cancer Prevention.” 2012. cancer.gov
- Mayo Clinic Staff. “Dietary fiber: Essential for a healthy diet.” Mayo Clinic. 2025. mayoclinic.org
- Harvard T.H. Chan School of Public Health. “Fiber.” The Nutrition Source. 2024. nutritionsource.hsph.harvard.edu
- U.S. Food and Drug Administration. “Daily Value on the Nutrition and Supplement Facts Labels.” 2024. fda.gov
- Electronic Code of Federal Regulations. “21 CFR 101.54: Nutrient content claims for good source, high, more, and high potency.” 2026. ecfr.gov
