The Fiber Hype: Does It Really Deserve All the Attention?

Esra Haidar ·

The Fiber Hype: Does It Really Deserve All the Attention?

Is fiber really worth all the attention? Does the body actually need it?

Many people believe that fiber is only useful for relieving constipation. In reality, dietary fiber is one of the most important nutrients affecting digestive health, heart health, blood sugar levels, and even beneficial gut bacteria.

First, what is dietary fiber?

Fiber is a type of carbohydrate found in plants. However, the human body cannot fully digest or absorb it in the same way it digests starches or sugars. As a result, fiber moves through the digestive system and performs several important functions.

Types of fiber

1- Soluble fiber

Soluble fiber absorbs water and forms a gel-like substance inside the intestines.

Its benefits include:

  • Slowing sugar absorption.
  • Reducing rises in blood sugar after meals.
  • Helping lower LDL cholesterol.
  • Increasing feelings of fullness.
  • Providing a preferred food source for beneficial bacteria in the colon.

Where is it found? Oats, barley, chia seeds, flaxseeds, legumes, apples, citrus fruits, carrots, and psyllium.

2- Insoluble fiber

Insoluble fiber does not dissolve in water. Its main functions include:

  • Increasing stool bulk.
  • Speeding up intestinal movement.
  • Reducing constipation.
  • Supporting regular bowel movements.

Where is it found? Wheat bran, whole grains, nuts, vegetables, and fruit skins.

Why does the body need fiber?

Fiber is not simply a “digestive regulator.”

It may help with:

  • Supporting colon health.
  • Reducing constipation.
  • Nourishing beneficial gut bacteria.
  • Producing short-chain fatty acids (SCFAs), such as butyrate, which is a primary energy source for colon cells and may help reduce inflammation and support the intestinal barrier.
  • Reducing the risk of heart disease.
  • Lowering cholesterol.
  • Improving insulin sensitivity.
  • Reducing the risk of type 2 diabetes.
  • Supporting weight management by increasing feelings of fullness.
  • Potentially reducing the risk of colon cancer when consumed as part of a balanced diet.

The relationship between fiber and beneficial gut bacteria

Many fermentable fibers act as prebiotics. When these fibers reach the colon:

  • Beneficial bacteria feed on them.
  • They produce compounds that may help reduce inflammation.
  • They support immune function.
  • They help maintain the integrity of the intestinal lining.
  • They may indirectly influence appetite regulation and metabolism.

This is why fiber is an essential part of maintaining a balanced gut microbiome.

How much fiber do we need each day?

General recommendations for adults are:

  • Women: 25 grams per day.
  • Men: 38 grams per day.

However, most people consume far less than the recommended amount.

Are fiber supplements better?

If a person obtains enough fiber from food, fiber supplements are generally unnecessary. However, if dietary intake is low or a specific condition requires additional fiber, a healthcare professional may recommend a supplement such as psyllium. Drinking enough water is important when using fiber supplements.

Is fiber suitable for everyone?

Not always. Some people may need to temporarily reduce a particular type or amount of fiber, including:

  • People with inflammatory bowel disease during an acute flare-up.
  • People with intestinal narrowing.
  • Some people with an intestinal obstruction.
  • Some people with gastroparesis.
  • Some people with irritable bowel syndrome (IBS). Symptoms may improve by reducing high-FODMAP foods rather than reducing all types of fiber. Fibers such as psyllium may be helpful, while other fibers may worsen symptoms in some individuals.

How can you increase fiber properly?

  • Increase your intake gradually over several days or weeks.
  • Drink enough water.
  • Include a variety of vegetables, fruits, legumes, and whole grains.
  • Do not rely on only one source of fiber.
  • A sudden increase may cause gas and bloating, especially in people who are not accustomed to eating much fiber.

In summary:

Fiber is not a dietary trend. It is an essential nutrient supported by strong scientific evidence. Its benefits are not limited to relieving constipation; fiber may also support heart health, blood sugar regulation, satiety, beneficial gut bacteria, and colon health. The key is not to consume the largest possible amount, but to choose the appropriate type and quantity and increase it gradually.

Dietitian Esraa Haider

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