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What Is oat fiber?

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Oat fiber contains zero carbs, fat or protein. In addition to insoluble and soluble fiber, whole grain oats are also plentiful in carbohydrates, protein, vitamins and minerals.

Nobody wants to worry about getting enough fiber in his or her diet. For this reason, let’s discuss what oat fiber really is, where it comes from and how it can benefit you.

What is oat fiber? Oat fiber is the inedible hull, hulk or outer shell of the oat grain. It is pure insoluble fiber which means that your body cannot digest any nutritional value, therefore it passes through the intestines undigested.

For anyone needing to enrich his or her body with extra fiber, then oat fiber may be the fix you are looking for. Each individual serving packs a hefty dosage of dietary fiber.

Oat fiber is virtually indigestible, and therefore it contains zero carbs and nutrients. The insoluble fiber helps reduce constipation, promotes a full feeling for long periods of time, and may help reduce overall LDL cholesterol.

what is oat fiber?

Where does oat fiber come from?

Oat fiber comes from the husk or hull of the oat grain. The whole oat grain is de-hulled to separate the oat groats, which is further processed to make different types of oats.

Oats are a whole grain, however, oat fiber comes from the fibrous husk of the oat. The husk or hull of the oat is pure insoluble fiber.

Therefore, oat fiber is manufactured byproduct that results from the process of separating oat groats from the inedible hull.

What is oat fiber made of? Grinding the hull or outermost protective layer of the oat grain makes oat fiber. The husk is considered a rich source of insoluble dietary fiber because it consists mainly of lignin, cellulose and hemicellulose.

Is oat fiber gluten-free? Yes, oat fiber is gluten-free just like the rest of the whole grain. However, the main concern lies within the growing, harvesting and production of the product.

Most agricultural equipment is used for multiple purposes, and therefore can be tainted from previous harvests. Products that are deemed gluten-free must use processing equipment that is completely separated from gluten cross contamination.

Is oat fiber the same as oatmeal?

No, oatmeal and oat fiber are not the same thing. Grinding the husk or hull of the oat grain makes oat fiber. Oatmeal is derived from the de-hulled oat groat.

Is oat fiber a whole grain? No, oat fiber is not a whole grain, but rather the outer hull or husk of the oat grain.

The grain is processed to separate the hull and the oat groat. Then, the hull is ground into a fine powder called oat fiber.

The oat groat may then be further processed into steel cut, rolled, quick, instant and Scottish oats. Each step of the process produces a varying result in taste, texture and consistency.

Are oat bran and oat fiber the same thing? The oat bran and oat fiber come from different parts of the grain.

The oat bran is the outermost part of the oat groat. The coating is the edible endosperm, which contain soluble and insoluble fiber, fat and protein. The oat bran contains a higher percentage of fiber in relation to oatmeal, however, the rest of the nutrition value remains similar.

Is oat fiber soluble or insoluble fiber?

Although oats and oatmeal are a terrific source of both soluble and insoluble fiber, oat fiber is not. Oat fiber consists almost entirely of insoluble fiber, which does not absorb or dissolve in water and passes through our digestive system nearly intact.

Is oat fiber soluble? Whole grain oats contain a balanced ratio of soluble fiber, but oat fiber is comprised of virtually indigestible insoluble fiber.

Does oat fiber have carbs?

Oat fiber nutrition information

Yes oat fiber has carbs, but the body is not able to process the carbohydrates into accessible calories. Oat fiber is almost entirely insoluble dietary fiber and contains a minimal amount of soluble fiber.

Oat fiber lacks any nutrients for the body to process as calories. As a result, it is the perfect ingredient for low-carb baking!

Does oat fiber raise blood sugar? Because oat fiber purely consists of insoluble dietary fiber, there are practically zero digestible carbohydrates. As a result, oat fiber does not contain glucose or raise blood sugar levels.

Is oat fiber okay for keto diet? Yes, oat fiber is okay for anyone on a low-carb or keto diet. Oat fiber helps by adding bulk to a recipe when the sugar is removed.

Oat fiber works well when sticking to a low-carb routine while still enjoying the occasional keto diet baked goods.

Oat Fiber Benefits 

Oat fiber is a fantastic source of insoluble fiber that offers many nutritional benefits and functional uses. Oat fiber absorbs both lipids and water that provides softness and texture to finished products. 

It also supports digestive health, heart health, boosts yields, and serves a purpose in foods like cereals, breads, pancakes, snacks, smoothies, bars, and meat products.

Oat fiber is loaded with insoluble fiber which helps people who face chronic constipation and need help removing toxic waste out of the body. This is an important component to maintain gastro intestinal health by regulating the flow of stool through the GI tract.

This allows your intestines to focus on optimal digestion of nutrients and also helps to prevent constipation. Fiber oats reduce cholesterol problems and cardiovascular risk.

Insoluble fiber acts as a bulking agent that eases flow and allows the stool to gently pass though the body. In addition, the fiber helps you to feel full for lengthier amounts of time, which can reduce hunger cravings that lead to excess eating and thereby promote weight loss.

Where to buy oat fiber

Oat fiber is often times located in the baking section at the supermarket. Not all markets will carry oat fiber, as it remains fairly uncommon consumer item. 

For a specialty item like this, it is often times more convent to order online. We love Anthony’s Organic Oat Fiber as it is non GMO and also keto friendly. Give it a try and let us know what you think!

Does Walmart sell oat fiber? Yes, Walmart sells Nunaturals Oat Fiber. You can order it online and occasionally find it in your local superstore.

Does oat fiber expire?

Oat fiber is shelf stable for approximately 2 years when stored in ideal conditions that are cool, dark and dry. Use airtight containers and pest prevention techniques.

This post details proper measure for how to store oatmeal in order to fully extend the shelf life as much as possible.

What do you use oat fiber for?

Oat fiber lacks any dietary value because it is fundamentally indigestible. As a result, it is low in available carbohydrates and nutrients.

How do you use oat fiber? Oat fiber works well in both baking and cooking applications. In addition, it is an effective way to boost fiber intake without consuming caloric value.

What does oat fiber do in a recipe? Oat fiber absorbs up to seven times its weight in water, which makes it useful for baking and a viable filler for ground meats.

What is a substitute for oat fiber? Oat flour can be substituted for oat fiber in most baking recipes. There is a fundamental difference in the absorption rate within liquids, however the difference should be negligible.

Vice versa, oat flour can easily be substituted for the sugar within most baking recipes. This will help to maintain the volume, without adding unnecessary caloric ingestion.

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Wednesday 25th of January 2023

I find oat fibre to be extremely beneficial to my digestion.


Wednesday 23rd of November 2022

How do you make smooth oatmeal


Wednesday 23rd of November 2022

Try using oat flour, or put rolled oats in a powerful blender and pulse until the oats are finely ground. Then, use the prepared oats to make a smooth oatmeal.


Monday 14th of March 2022

I understand what Oat Fibre is, but would it be considered AIP compliant?


Tuesday 15th of March 2022

I recommend speaking with a dietician or physician that is more familiar with your case. Kind regards

Karam Hanna

Tuesday 31st of August 2021

We want to produce Pasta and Macaroni, but not with regular ingredients, we want to use Lupine and Chickpea flour, combine with Semolina and Oat fiber and Vital wheat Gluten. We want to use Oat Fiber to increase the amount of fiber to reduce the Net carbohydrate in the final product That is why I need your help from all your experience. My goal is to make low Carbohydrates Pasta, for overweight and diabetic people. I want to ask about the right dough recipe for manufacture Pasta from that kind of flour. I suggest Semolina, Lupin Flour, Oat Fiber, and Vital Wheat Gluten. Is it possible? Pasta that can be dried and sold in Packs like any normal Pasta. Please send me your opinion. Thanks and best regards.


Friday 3rd of September 2021

Thank you for reaching out, but this is a very specific set of questions that needs to be addressed by a recipe tester. I am interested in the project, but would need to get into the kitchen and try a variety of products. Let me know how it works out. Warmly, Joshua

Eunice Duddy

Saturday 15th of May 2021

Is Oat fibre suitable for chrontic constipation. Is it better than oat bran?


Sunday 16th of May 2021

Chronic constipation is a condition that you should speak to a physician about. What I can say is that oat fiber is mostly insoluble fiber. Your body cannot process insoluble fiber, therefore it passes through the digestive tract and helps to move stool along with it. Therefore, it is common that oat fiber will help prevent constipation. In contrast, oat bran contains both soluble and insoluble fiber. In general, fiber is extremely helpful in alleviating constipation and you should find relief in both solutions.