Say Goodbye to Fiber Distress!

by Shelby Burns, MS, RDN/LDN



It’s no secret that a healthy diet rich in fibrous foods and diverse nutrients helps to promote a healthy gut microbiome, which in turn allows for the proper digestion and utilization of nutrients in the diet. However, what can you do when fibrous foods such as fruits, vegetables, nuts, seeds, and beans cause you digestive distress?

In the article Gut Health and Nutrient Absorption, we talk about how it can be difficult to support the gut and optimize nutrient utilization when that gut has difficulty digesting the foods that aid in healing. Feeling bloated and overly full, suffering from abdominal cramps, or experiencing changes in bowel habits are quite common if you suddenly increase the amount of fiber in your diet.2



Why Fiber Can Be Tough to Consume

There are a few reasons that fiber can cause digestive distress. As fiber passes through the digestive system, some fibers are fermented, and one of the by-products of fermentation is gas. Some fiber passes through the digestive system without breaking down. This can also cause gas because bacteria in the colon produce gas as a by-product of their digestion of fiber. Fiber that is fermentable is known as soluble fiber, whereas insoluble fiber refers to fiber that is not digested or absorbed by the body.


Soluble Fiber

Soluble fiber dissolves in water. Gut flora can ferment soluble fiber, which allows good bacteria to populate the gut.1 As soluble fiber dissolves, it creates a gel that prevents dietary cholesterol from being broken down and digested, which may help to lower blood cholesterol. It can also promote feelings of satiety.

However, people who are very sensitive to the effects of this fermentation process may experience bloating, indigestion, and gas. The most famous culprits behind these effects are the short-chain carbohydrates called FODMAPs.

Soluble fiber sources include:

  • Apples
  • Barley
  • Beans*
  • Broccoli
  • Brussels sprouts
  • Carrots
  • Oats
  • Pears
  • Peas
  • Sweet potatoes



Insoluble Fiber

Insoluble fiber is not fermentable and does not dissolve in water. As a result, its benefits include adding bulk to stool and promoting regularity. Insoluble fiber usually does not cause as much digestive discomfort as soluble fiber. If increasing fiber intake has been causing digestive distress, it can be helpful to focus on including more insoluble fiber sources.

Insoluble fiber sources include:

  • Beans*
  • Cauliflower
  • Dark, leafy greens
  • Green beans
  • Nuts
  • Potatoes
  • Wheat bran
  • Whole wheat

*Soybeans, kidney beans, and pinto beans have high amounts of insoluble fiber, but beans are a great source of both types of fiber.



How to Begin Including More Nutrient-Dense Foods

When adding more fiber to the diet, it’s important to start slowly and increase water intake. This will minimize gas, bloating, and abdominal discomfort. The recommended daily intake of fiber for adults is about 25–30 grams per day; however, people who currently consume few fibrous foods may find this to be a drastic increase. Although whole foods are preferable, there are many nutrient-dense food options that will help to heal the gut. Adding small amounts of fiber to the diet may allow those who suffer from digestive distress to work up to including more fibrous foods.



Tips to minimize digestive distress while adding more fiber:

  • Canned fruits without skins (such as canned peaches or applesauce) often have less fiber than fresh, whole foods.
  • Avoid packaged, processed foods with added fiber. (The ingredients list might include chicory root or inulin.) These ingredients are often added to ice creams, nutrition bars, cereals, dairy products, and more.
  • Check out our low FODMAP food list. Low FODMAP fruits and vegetables can go a long way toward providing fiber and minimizing discomfort.
  • Try cooked or mashed fruits and vegetables. Cooking vegetables helps to break down the fiber.
  • Puréed or powdered fruits and vegetables are great additions to the diet because the fibers are already broken down.
  • Start with small portions of lower fiber foods, such as butternut squash/winter squash, carrots, or mushrooms, before diving into a heaping bowl of salad.

Start by trying 1 serving per day of 1–3 of these soft, lower fiber foods:

  • Applesauce
  • Butternut squash soup
  • Canned peaches or pears
  • Cantaloupe (orange melon)
  • Carrots
  • Watermelon or honeydew melon
  • Mushrooms
  • Seedless grapes
  • Very ripe banana
  • Whole wheat toast or crackers



Summing It Up

Eating fruits and vegetables is beneficial to digestion and overall health, so it can be frustrating when these healthful foods irritate the gut. Before deciding to avoid all fibrous foods, try some of the recommendations above. It may also be helpful to keep a diary to track foods consumed and any side effects that occur. It’s important to slowly increase fiber intake, try to reduce FODMAPs, cook foods thoroughly, and continue to consume even small amounts of fiber daily.



About the Author

Photo: Shelby Burns, MS, RD/LDN

Registered Dietitian Nutritionist Shelby Burns has been in the fitness and nutrition industries for more than ten years. Shelby, who has personally struggled with gut issues, believes that exceptional wellness starts from within. Her passion for helping people prioritize their health shines through as she assists Ixcela clients in making diet and lifestyle shifts that result in renewed energy, better sleep, and improved digestion. 

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Interested in learning more about Ixcela? Check out Ixcela’s test, to receive personalized nutrition, supplement, mindfulness, and fitness fitness recommendations based on the metabolites we test to improve energy, GI health, mood, and overall wellbeing.




Sources Used:

  1. Jha, Rajesh, and Julio F. D. Berrocoso. “Dietary Fiber and Protein Fermentation in the Intestine of Swine and Their Interactive Effects on Gut Health and on the Environment: A Review.” Animal Feed Science and Technology, vol. 212, 2016, pp. 18–26. Crossref, doi:10.1016/j.anifeedsci.2015.12.002.
  2. “Dietary Fiber: Essential for a Healthy Diet.” Mayo Clinic, 6 Jan. 2021, https://www.mayoclinic.org/healthy-lifestyle/nutri...