Types of Fiber: Soluble Vs. Insoluble Fibers

Types of Fiber: Soluble Vs. Insoluble Fibers

Newsflash, people: fiber is cool again.

Fiber is one of the nutrients your body needs to maintain gut health and bowel functioning. Whether your fiber comes from plants, grains, or other sources, your body is glad you ate it!

But many people have questions about fiber, what it is, and how exactly fiber contributes to a healthy body.

A lot of this confusion stems from one thing—that there are actually two kinds of fiber that are important for your body. Understanding how both types of fiber impact your body and contribute to a healthy life is essential to appreciating fiber for all it does.

Strap in for our VINA guide to the two types of fiber and how they work together with your digestive tract to keep you regular, happy, and healthy.

What Is Fiber, Anyway?

Before we tackle the two different kinds of fiber, we should start by answering the basic question: what is fiber, anyway?

Fiber is the indigestible part of carbohydrates that our bodies cannot break down and use as fuel. Most fiber comes from plants, vegetables, fruits, legumes and beans, and whole grains.

This might be confusing to you. After all, how can a food that our bodies cannot use be healthy for us?

While our bodies may not be able to break down fiber to use as energy, the microbiota living in our gut can. In fact, fiber is the main source of fuel for these trillions of bacteria and microorganisms that live in your digestive tract.

You may be surprised to learn that there are more microorganisms living in your gut than there are cells in your body! Feeding these microorganisms properly can support digestion, weight maintenance, blood sugar regulation, immune system functions, and even brain activity and mental health.

Eating enough fiber is essential to promote the health of the good gut bacteria that support healthy bodily functioning. This is because most carbs, fats, and proteins our bodies use as fuel are digested before the healthy bacteria has a chance to eat. 

Since fiber can’t be digested by our bodies, when we eat enough fiber, we ensure that our healthy gut bacteria are getting the nutrition they need to remain functional. If you find that you’re not getting enough fiber in your diet, there are also dietary supplements that you can incorporate into your routine, although it’s worth discussing with your doctor first. 

The Two Types of Fiber

Now that we understand a little bit more about the importance of fiber, we are ready to separate the two types of fiber.

Fiber can generally be broken down into two subcategories: soluble fiber and insoluble fiber. As the names suggest, soluble fiber dissolves in water, while insoluble fiber does not. This has a major impact on your gut bacteria, as they can only typically digest soluble fiber, while insoluble fiber passes right through your digestive system, where it serves as a bulking agent for stool. Good sources of insoluble fiber include vegetables and whole grains. 

Soluble fiber, on the other hand, dissolves in the liquids in our digestive tract, where the good gut bacteria have a chance to use it as fuel. Most foods that contain fiber contain both soluble and insoluble fiber, but it is important to know that not all fiber is the same. You’ll find soluble fiber in barley, oat bran, bananas, lentils, and much more. 

Consuming both types of fiber is essential to promoting good health, and consuming enough fiber is the best thing you can do to encourage a healthy gut microbiome.

What Does Fiber Do For Your Body?

While fiber serves as the main source of fuel for your gut microbiome, we have yet to go much in-depth on how fiber actually helps your body and your gut microbiome. So here are a few health benefits of consuming soluble and insoluble fibers and the kind of impact they can make on your health.

Fight Blood Sugar Spikes

Eating foods high in fiber can have a balancing effect on blood sugar spikes after eating. This may have to do with the fact that foods that are high in fiber typically have a lower glycemic index than carbohydrate food sources with less fiber.

This impact on blood sugar spikes also seems to be primarily seen in foods that contain high amounts of soluble fiber, rather than insoluble.

If you are diabetic or otherwise concerned about spikes in your blood sugar, then focusing on high soluble fiber carbohydrate sources over refined carbs can have a major impact on your ability to control and manage blood sugar spikes.

Help Aid Weight Loss by Promoting Satiety

Studies seem to indicate that foods that are high in fiber tend to have a larger impact on fullness and satiety.

Researchers believe this could be due to fibers' ability to absorb water in the intestines, which can give a stronger feeling of fullness in the gut.

Once again, this impact is mainly seen with soluble fiber rather than insoluble fiber—not all fiber is equal when considering the impact on fullness.

Fiber May Prevent or Slow Development of Colorectal Cancer

While the research is still relatively young, there appears to be a relationship between eating a diet that is high in fiber and lower levels of colorectal cancer.

While the relationship is not the strongest in the world, there is evidence to suggest that eating a high fiber diet can help reduce your likelihood of developing colorectal cancer.

Another thing to be aware of when looking at these connections, however, is that the best sources of fibers, like vegetables, fruits, and whole grains, often have other healthy nutrients like antioxidants and other nutrients that positively impact your overall health. It is difficult to separate these health impacts to see what is actually causing the drop in cancer rates amongst those who eat a diet rich in fiber.

That said, eating a diet that is rich in soluble fiber is a great choice for a healthy lifestyle.

Fiber Can Lower Cholesterol, Albeit Marginally

Eating a diet that’s higher in fiber can also lower cholesterol levels in the blood, but not by a huge amount.

This review of 67 studies found that consuming up to ten grams of soluble fiber per day can reduce total cholesterol by 1.7mg/dl and bad cholesterol by as much as 2.2mg/dl. While this is a measurable impact, it is not a huge impact and may not be enough to significantly lower cholesterol in people with high cholesterol levels.

Some studies show a larger impact on cholesterol levels depending on the specific type of fiber used and its solubility. However, the overall research seems to indicate that the impact of fiber on cholesterol is positive but small.

Soluble Vs. Insoluble Fiber Takeaways

Fiber is the part of carbohydrates that our bodies cannot digest and use as fuel themselves. Instead, this fiber is passed through our digestive system.

There are two types of fiber: soluble and insoluble. Soluble fiber dissolves in water and can be used as fuel for our gut microbiome, while insoluble fiber does not dissolve in water and passes through our digestive tract intact, where it serves as a bulking agent for stool.

Consuming enough fiber is essential to feeding our gut bacteria, which perform a whole slew of important functions for our bodies, ranging from blood sugar regulation to immune system functioning.

On top of this, there are other benefits to consuming high amounts of fiber, like decreased cholesterol, increased satiety, and a potential decrease in the likelihood of colorectal cancer.

If you are looking for a way to consume more fiber, give VINA prebiotic sodas a try! Our sodas are packed with prebiotic fiber to help give your gut a boost and feed your body the right way. Plus, our sodas are flavored with stevia, a natural sugar replacement, and natural flavors and fruit juices so that you finally have a healthy soda option that works with your body.

Give VINA a try today, and check us out for more great content like this.



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Dietary fiber intake and risk of colorectal cancer and incident and recurrent adenoma in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial | NCBI 

Dietary fiber and energy regulation | NCBI

Understanding the Physics of Functional Fibers in the Gastrointestinal Tract: An Evidence-Based Approach to Resolving Enduring Misconceptions about Insoluble and Soluble Fiber | NCBI

Fiber | Academy of Nutrition and Dietetics

Questions and Answers on Dietary Fiber | Food and Drug Administration