High-Fiber Keto Foods: 12 Constipation-Busting Options
Diet & NutritionKetogenic Diet

The 12 Best Sources of Fiber on the Keto Diet

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Updated on April 1, 2026
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best sources of fiber on keto
Adherence to the keto diet doesn’t have to mean neglecting your digestive health.

One thing that’s often missing from the keto diet? A little bit of roughage. The popular diet, which typically requires you to get up to 80 percent of your calories from fat and only 20 to 50 grams (g) of carbohydrates per day, is often criticized for its lack of fiber.

However, that’s only part of the story, and you can still meet your daily fiber requirements by including some of these high-fiber, low-carb foods in your diet.

Why Is Fiber so Important if You’re on Keto?

If you don’t plan your keto diet the right way, you might wind up short on fiber. “A poorly planned keto diet is at risk of being deficient in fiber,” says Dana Elia, RDN, an integrative and functional medicine dietitian in Lancaster, Pennsylvania. She notes that dietitians frequently see patients who complain of constipation when they start eating keto.

The thing is, most Americans don’t get enough of the GI-friendly nutrient anyway, according to the U.S. Department of Agriculture (USDA).

 More than 90 percent of women and 97 percent of men don’t meet the recommended daily amount of fiber. Ruling out most carbohydrate sources, including whole grains, fruits, and legumes, increases the likelihood of fiber deficiency.

Why Do You Need Fiber?

Fiber plays a key role in digestive health. Because your body doesn’t digest fiber, it passes through your system and keeps you regular by softening and adding bulk to your stool.

 And some fiber has benefits beyond bowel movements: It feeds the good bacteria in your GI tract, aiding healthy digestion and nutrient absorption. It also helps lower cholesterol by increasing the excretion of the cholesterol you eat.

“The digestive tract is where your body’s second brain is, and it’s home to the majority of your immune system,” says Elia. “If you’re following keto, it should be one of your biggest priorities to make sure you get adequate fiber to keep your gut healthy and happy,” she adds. And, she notes, high-fat diets slow digestion and decrease GI motility, making it crucial to get enough fiber.

Particularly if you’re on specific drugs, like proton pump inhibitors for heartburn, you may notice changes in your digestion if you transition to a high-fat diet, says Elia.

How Much Fiber Do You Need Every Day?

The USDA’s 2020–2025 Dietary Guidelines for Americans sets a goal of 28 to 34 g of fiber a day, depending on age, sex, and pregnancy status.

 Following a keto diet food list doesn’t mean it’s impossible to get what you need, but you have to remain diligent and determined to make it happen, says Keri Glassman, RDN, who is in private practice in New York City.
Many fiber-rich foods contain few net carbs — that is, total carbs minus fiber and sugar alcohols. However, it’s worth noting that the U.S. Food and Drug Administration doesn’t recognize net carbs as an accurate measurement of carb intake.

That said, maintaining a low overall carb intake keeps you in ketosis, the metabolic state that causes your body to burn fat instead of carbs. Here are 12 foods that can help keep your fiber intake up without derailing your keto goals.

1

Avocado

avocado
“All keto followers should consume avocados, because they’re a great source of fiber and fat,” says Elia. Half an avocado contains just 1.4 net carbs, but a whopping 5 g of fiber.

2

Chia Seeds

chia seeds
One ounce (oz) of chia seeds offers 9.6 g of fiber (and a net carb total of 2.2 g).

 You can make chia seed pudding by mixing the seeds with liquid, creating a gel-like substance that you can enjoy mixed with fruits, natural sweeteners like honey, and your choice of spices. Glassman suggests sprinkling chia into small, low-carb smoothies or onto oatmeal, eggs, or a salad.

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3

Pecans

pecans
Nuts can be a great option on the keto diet because of their fiber and fat content, says Glassman. Pecans are among the lowest-carb nuts, with just 1.2 net carbs per oz (19 halves).

 That serving also supplies 2.7 g of fiber.
4

Almonds

almonds
Almonds are another good choice. One of the most fiber-rich nuts, they clock in at 3.54 g fiber (and about 2.5 g of net carbs) per oz (23 whole kernels).

5

Flaxseed

flaxseed
These small seeds make a killer crunchy coating for fish or chicken in lieu of breading, says Glassman. To better absorb the nutrients in flax, make sure they’re ground — you’ll reap the heart-healthy, cholesterol-lowering benefits of flaxseed’s high omega-3 fatty acid content.

 The USDA reports that 1 tablespoon of ground flax boasts 2 g fiber and close to 0 g net carbs — so, basically, it’s a freebie.

6

Collard Greens

collards
Starchy veggies like sweet potatoes are notoriously off-limits on keto, but there are plenty of keto-friendly greens. Target high-fiber picks like collards, says Elia. They cook down nicely, so go for cooked rather than raw greens to get in more fiber per cup. One 130-g cup of cooked collards has about 2 g of net carbs and 5.6 g of fiber.

7

Cauliflower

cauliflower
Cauliflower is having a moment — and that’s great news for keto diet followers. A 1-cup (107 g) serving of this low-carb veggie has only about 3 g of net carbs and 2 g of fiber, according to the USDA.

Plus, it’s super versatile: You can use it to make cauliflower pizza crust, chop it small to stand in for rice, mash it to replace mashed potatoes, and blend it into creamy soups.

8

Pumpkin Seeds

pumpkin seeds
One ounce of dried pumpkin seed kernels yields a little more than 1 g of net carbs and 1.7 g of fiber.

 Plus, they’re simple to grab as a handful for a snack, so you can sneak a bit more fiber into your day. These recipes can help you get started.
9

Coconut

coconut
A small piece of coconut meat (about 2 inches by 2 inches) offers just under 2.8 g of net carbs and 4 g of fiber.

“Plus, it goes double duty to help you get more fat,” says Elia. Look for this in the frozen section at some grocery stores. If you can’t find it near you, go for unsweetened shredded coconut.

10

Raspberries

raspberries
It can be tough to figure out how to fit fruit into a keto diet, but raspberries are a particularly good choice because of their fiber content. A half cup of fresh raspberries (weighing around 61.5 g) provides 4 g of fiber and 3.3 g of net carbs.

Consider cooking down frozen raspberries and using them as a syrupy topping on keto pancakes.

11

Artichokes

artichoke
Artichokes are a surprisingly good option for getting more fiber into your keto diet. One half-cup of artichoke hearts, weighing 84 g, provides 4.79 g of fiber and less than 4.31 g of net carbs.

Add them as a topping to a keto pizza, roast or grill fresh artichokes, or bake them with keto-friendly cheese as an appetizer.

12

Sauerkraut

sauerkraut
Fermented foods — packed with probiotics — are good for your gut, full of flavor, and low in carbohydrates. Half a cup of sauerkraut, or 71 g, supplies 2 g of fiber and a little more than 1 g of net carbs.

Plus, you can use it to add a tangy flavor boost to whatever you’re eating, from cuts of meat to salads.

13

Bonus: Green Smoothies

green smoothie

Many of the above foods can be added to a fiber-packed smoothie, says Glassman. Tossing in frozen spinach, zucchini, or cauliflower (like cauliflower rice) adds fiber, vitamins, and minerals for a respectable amount of carbs.

While zucchini or cauliflower may seem like strange smoothie additions, they impart a creamy texture without a strong vegetable taste. Chia seeds are also great in smoothies.

Just go easy on the size of the smoothie to be sure not to kick yourself out of ketosis.

When to See a Doctor About Constipation on Keto

Fiber is essential for everyone, regardless of your eating plan. If you’re going keto, your best — and safest — course of action is to enlist a registered dietitian who is knowledgeable about the diet to design a plan that meets your nutrient needs, says Elia.

Constipation is defined as fewer than three bowel movements a week, or stools that are hard and dry or difficult to pass.

 If increasing your fiber intake, drinking more water, and being physically active don’t help move things along, talk to your doctor.

The Takeaway

  • Including fiber-rich, low-carb foods such as avocados, chia seeds, and almonds in your keto diet can help address common adverse effects like constipation.
  • While a high fiber intake is achievable on keto, it’s best to consult a knowledgeable registered dietitian to develop a balanced plan that is tailored to your nutritional needs.
  • Boosting fiber intake with foods like sauerkraut and green smoothies not only supports metabolism but also promotes gut health, which is crucial for overall well-being.
  • Should constipation persist despite dietary changes, seek guidance and evaluation from a healthcare professional.
EDITORIAL SOURCES
Everyday Health follows strict sourcing guidelines to ensure the accuracy of its content, outlined in our editorial policy. We use only trustworthy sources, including peer-reviewed studies, board-certified medical experts, patients with lived experience, and information from top institutions.
Resources
  1. Dietary Guidelines for Americans 2020–2025. U.S. Department of Health and Human Services. December 2020.
  2. Dietary fiber: Essential for a healthy diet. Mayo Clinic. December 11, 2024.
  3. Get to Know Carbs. American Diabetes Association.
  4. Avocado, raw. USDA FoodData Central. October 30, 2020.
  5. Seeds, chia seeds, dried. USDA FoodData Central. April 1, 2019.
  6. Nuts, pecans. USDA FoodData Central. April 1, 2019.
  7. Nuts, almonds. USDA FoodData Central. April 1, 2019.
  8. Does ground flaxseed have more health benefits than whole flaxseed? Mayo Clinic. January 31, 2023.
  9. Seeds, flaxseed. USDA FoodData Central. April 1, 2019.
  10. Collards, fresh, cooked, no added fat. USDA FoodData Central. October 28, 2022.
  11. Cauliflower, raw. USDA FoodData Central. April 1, 2019.
  12. Seeds, pumpkin and squash seed kernels, dried. USDA FoodData Central. April 1, 2019.
  13. Nuts, coconut meat, raw. USDA FoodData Central. April 1, 2019.
  14. Raspberries, raw. USDA FoodData Central. April 1, 2019.
  15. Artichokes, (globe or french), cooked, boiled, drained, without salt. USDA FoodData Central. April 1, 2019.
  16. Sauerkraut, canned, solids and liquids. USDA FoodData Central. April 1, 2019.
  17. Definition and Facts for Constipation. National Institute of Diabetes and Digestive and Kidney Diseases. May 2018.
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