In this article
- Blackberries fiber by the handful and by the cup
- The seeds are where much of the fiber lives
- Blackberries next to other berries and everyday fruit
- Why blackberries count among the antioxidant berries
- Fresh, frozen and blackberry preserves compared
- A breakfast toast swap, by the numbers
- Blackberries, gut health and blood sugar
- Easy ways to work a cup of blackberries into your day
- Buying, rinsing and storing blackberries
- A simple rule for picking your blackberries
- Questions about blackberries and fiber
- Sources
A cup of fresh blackberries delivers about 7.6 grams of fiber for only 62 calories. The surprising part is the balance, since that same cup holds about 7 grams of sugar, so blackberries fiber actually edges out the sugar.
Plenty of popular fruits run the other way. A large apple carries about 25 grams of sugar and 5 grams of fiber, according to the FDA, while blackberries flip that ratio and rank among the best berries high in fiber.
Blackberries fiber by the handful and by the cup
USDA FoodData Central gives these values for raw blackberries:
| Amount | Calories | Fiber | % Daily Value | Total sugars |
|---|---|---|---|---|
| 100 grams | 43 | 5.3 g | 19% | 4.9 g |
| 1/2 cup (72 g) | 31 | 3.8 g | 14% | 3.5 g |
| 1 cup (144 g) | 62 | 7.6 g | 27% | 7.0 g |
| 2 cups (288 g) | 124 | 15.3 g | 55% | 14.1 g |
The FDA counts a food as high in a nutrient when one serving gives 20% or more of the Daily Value. A single cup of blackberries clears that bar for fiber with room to spare.
Cleveland Clinic notes that a cup holds roughly 15 to 16 berries, depending on size. That means each berry carries about half a gram of fiber.
Not sure how many grams your own day should include? Our fiber calculator turns a few details about you into a personal target.
The seeds are where much of the fiber lives
Each blackberry is a cluster of tiny fruit segments, and every segment holds a small seed. According to Cleveland Clinic, most of the insoluble fiber in blackberries sits in those seeds.
Insoluble fiber is the kind that doesn’t dissolve in water. It adds bulk and helps keep waste moving through your digestive tract.
Blackberries also carry soluble fiber, which dissolves into a gel. Cleveland Clinic credits this type with helping lower LDL, often called bad cholesterol.
That mix of both fiber types is part of what makes blackberries useful for gut health. You get the bulk from the seeds and the gentler, gel-forming fiber from the flesh.
It also explains why seedless blackberry products deserve a second look. Once the seeds are strained out, a large share of the insoluble fiber goes with them, even if the flavor stays.
Blackberries next to other berries and everyday fruit
Dietary Guidelines for Americans portions make the comparison on fiber per calorie easy to see:
| Fruit and serving | Calories | Fiber | Fiber per 100 calories |
|---|---|---|---|
| Raspberries, 1 cup | 64 | 8.0 g | 12.5 g |
| Blackberries, 1 cup | 62 | 7.6 g | 12.3 g |
| Boysenberries, 1 cup | 66 | 7.0 g | 10.6 g |
| Wild blueberries, 1 cup | 80 | 6.2 g | 7.8 g |
| Strawberries, 1 cup | 49 | 3.0 g | 6.1 g |
| Pear, 1 medium | 103 | 5.5 g | 5.3 g |
| Apple with skin, 1 medium | 104 | 4.8 g | 4.6 g |
| Blueberries, 1 cup | 84 | 3.6 g | 4.3 g |
| Banana, 1 medium | 112 | 3.2 g | 2.9 g |
Blackberries sit just a hair behind raspberries and well ahead of the fruits most people keep on the counter. A cup gives about 2.4 times the fiber of a banana for roughly half the calories.
Against regular blueberries, the gap is wider still. You’d need more than two cups of blueberries to match the fiber in one cup of blackberries.
Why blackberries count among the antioxidant berries
The deep purple-black color comes from anthocyanins, a group of plant pigments in the polyphenol family. Cleveland Clinic describes blackberries as especially full of them.
Research suggests anthocyanins may help protect the heart and blood vessels, though their direct effect on blood pressure is still being studied. Early studies cited by Cleveland Clinic also link them to better blood flow to the brain and improved memory in people with mild to moderate dementia.
Those findings are promising rather than settled. Still, they add to the case for eating dark berries regularly alongside their fiber.
Vitamins and minerals in a cup
A one cup serving (144 grams) of raw blackberries also supplies, per USDA:
- Manganese: about 0.9 mg, roughly 40% of the 2.3 mg Daily Value.
- Vitamin C: about 30 mg, roughly 34% of the 90 mg Daily Value.
- Copper: about 0.24 mg, roughly 26% of the Daily Value.
- Vitamin K: about 29 micrograms, roughly 24% of the 120 microgram Daily Value.
- Protein: about 2 grams.
That’s three nutrients above the 20% high mark in one cup, on top of the fiber.
Fresh, frozen and blackberry preserves compared
Blackberries come fresh, frozen and as jam, and the form changes the numbers more than you might expect.
| Form and serving | Calories | Fiber | Total sugars |
|---|---|---|---|
| Fresh, 1 cup (144 g) | 62 | 7.6 g | 7.0 g |
| Frozen unsweetened, 1 cup (151 g), USDA | 97 | 7.6 g | 16.1 g |
| Frozen organic, Woodstock, 3/4 cup (140 g) | 90 | 7 g | 15 g |
| Blackberry preserves, Bonne Maman, 1 Tbsp (20 g) | 50 | not declared | 13 g |
| Seedless preserves, Kroger, 1 Tbsp (20 g) | 50 | not declared | 9 g (8 g added) |
USDA’s frozen unsweetened record and the Woodstock bag both keep about the same fiber as fresh. Their listed sugar and calories run higher, and USDA’s frozen record also lists much less vitamin C, at about 5 mg per cup versus 30 mg in fresh.
Preserves are a different story. A tablespoon of jam brings mostly sugar, and neither brand above declares any fiber on its label.
Seedless versions strain out the seeds, which is where Cleveland Clinic says most of the insoluble fiber sits. The Kroger seedless jam also lists high fructose corn syrup and corn syrup right after the berries.
Want more ways to cook and bake with blackberries? Our recipe eBooks are packed with simple high fiber breakfasts, salads and desserts.
A breakfast toast swap, by the numbers
Picture your usual morning toast spread with a tablespoon of blackberry preserves. That topping adds about 50 calories and 13 grams of sugar, with no fiber listed.
Now mash half a cup of fresh blackberries with a fork and spread that on the toast instead. You get about 3.8 grams of fiber and 3.5 grams of natural sugar for roughly 31 calories.
The swap cuts the topping’s calories by more than a third and its sugar by almost three quarters. Your toast also gains about 14% of the day’s fiber before you count the bread.
Blackberries, gut health and blood sugar
The insoluble fiber in blackberries helps prevent constipation and bloating by keeping things moving, according to Cleveland Clinic. Their glycemic index is about 25, which points to a slow, steady rise in blood sugar rather than a spike.
Low sugar and high fiber also make blackberries friendly for lower carb eating. A cup has about 13.8 grams of carbohydrate, and subtracting the 7.6 grams of fiber leaves roughly 6 grams of net carbs.
If you’re adding a lot of berries at once, ease in. Harvard’s Nutrition Source recommends increasing fiber gradually and drinking plenty of fluids so your gut has time to adjust.
If your digestion could use some support, our gut health guides lay out the daily habits that help most.
Easy ways to work a cup of blackberries into your day
Cleveland Clinic notes that experts recommend about two servings of fruit a day. A cup of blackberries is an easy way to cover one of them, and it travels well into almost any meal.
- Yogurt parfait: layer a cup of blackberries with plain yogurt and 1 tablespoon of chia seeds for about 11.7 grams of fiber.
- Green salad: toss a handful of berries with spinach, walnuts and a light vinaigrette for a sweet, tart contrast.
- Smoothie: blend frozen blackberries whole so the seeds, and their insoluble fiber, stay in the glass.
- Warm topping: simmer a cup of berries for a few minutes until they slump, then spoon them over pancakes in place of syrup.
Blending keeps the seeds in play. If the texture bothers you, blend longer rather than straining, since the strainer is exactly where the seeds and much of their fiber end up.
Buying, rinsing and storing blackberries
Look for berries that are plump, glossy and evenly dark. Check the bottom of the container for crushed or moldy fruit before you buy.
Rinse blackberries just before eating, as Cleveland Clinic recommends washing them first. Until then, keep them dry in the refrigerator in their original container.
To freeze your own, spread rinsed and dried berries on a tray until firm, then move them to a bag. They’ll keep their fiber and are ready for smoothies, oatmeal or baking.
A simple rule for picking your blackberries
- If blackberries are in season and you’ll eat them within a few days: buy fresh for the most vitamin C and the lowest sugar.
- If you want fiber on hand all year: keep a bag of frozen unsweetened blackberries, which hold onto about 7 grams per serving.
- If you love jam: treat it as flavor, not a fiber source, and check the label for corn syrup and added sugars.
- If fiber is your main goal at breakfast: mash fresh or thawed berries onto toast or stir them into oatmeal instead of spreading preserves.
Questions about blackberries and fiber
How much fiber is in a cup of blackberries?
A cup of raw blackberries (144 grams) has about 7.6 grams of fiber. That’s 27% of the 28 gram Daily Value for only 62 calories.
Are blackberries one of the berries highest in fiber?
Yes. Per cup, blackberries trail only raspberries among common berries, at 7.6 grams versus 8.0 grams, and they beat blueberries and strawberries by a wide margin.
Do frozen blackberries have as much fiber as fresh?
Yes. USDA’s frozen unsweetened blackberries list about 7.6 grams of fiber per cup, the same as fresh, though they list more sugar and less vitamin C.
Are blackberries good for gut health?
Their fiber helps. Cleveland Clinic says the insoluble fiber, mostly in the seeds, helps prevent constipation and bloating, while soluble fiber helps lower LDL cholesterol.
Are blackberries antioxidant berries?
Yes. They’re especially rich in anthocyanins, the pigments behind their dark color, and they also supply vitamin C and manganese.
Is blackberry jam a good source of fiber?
No. Common blackberry preserves don’t declare fiber on their labels, and a tablespoon carries 9 to 13 grams of sugar.
Are blackberries low in carbs?
Fairly. A cup has about 13.8 grams of carbohydrate, and subtracting 7.6 grams of fiber leaves about 6 grams of net carbs.
Sources
- U.S. Department of Agriculture, Agricultural Research Service. “Blackberries, raw (173946); Blackberries, frozen, unsweetened (171710); Branded Foods: Woodstock Organic Whole Blackberries (2139463); Bonne Maman Blackberry Preserves (1857545); Kroger Seedless Blackberry Preserves (2533426).” FoodData Central. 2019 to 2026. fdc.nal.usda.gov
- U.S. Food and Drug Administration. “Daily Value on the Nutrition and Supplement Facts Labels.” 2024. www.fda.gov
- U.S. Department of Agriculture and U.S. Department of Health and Human Services. “Food Sources of Dietary Fiber.” Dietary Guidelines for Americans, 2020 to 2025. www.dietaryguidelines.gov
- U.S. Food and Drug Administration. “Raw Fruits Poster (Text Version / Accessible Version).” 2023. www.fda.gov
- Cleveland Clinic. “8 Benefits of Blackberries.” Health Essentials. 2026. health.clevelandclinic.org
- Harvard T.H. Chan School of Public Health. “Fiber.” The Nutrition Source. 2022. nutritionsource.hsph.harvard.edu
