Your Body Needs More Fiber: Understand The Health Benefits


Updated on: February 14, 2020

You’ve probably heard about the importance of fiber in your diet. But if you’re like most North Americans, you’re not getting nearly as much as you should. (7)

That’s because the typical Western diet is high in sugar and fat (particularly animal fat), and generally low in sources of fiber such as fruit and vegetables. (17) For many individuals, convenience is the name of the game when they’re hungry. We grab food that’s fast and easy, rather than what our bodies need. And that’s very true when it comes to fiber.

But the good news is that it’s quite easy to increase your fiber intake. In this article, we’ll talk about the role of dietary fiber and its important health benefits, as well as how to get more fiber in your diet.

What is fiber?

Dietary fiber is the part of plant foods that is resistant to digestion and absorption in the small intestine. Instead, it travels to the large intestinal to undergo partial or full fermentation and then it is excreted in your stool. (5) Fiber is also sometimes referred to as roughage or bulk.

Types of fiber

There are two types of fiber: soluble fiber and insoluble fiber. You may wonder which type of fiber is better for you, but the truth is that each type of fiber has a role in your diet.

apple, oats in a bowl and milk on a table

Both types of fiber – soluble and insoluble – have a significant role to play in your diet.

Soluble fiber

This is the type of fiber that can dissolve in water, forming a gel-like consistency. You’ll find soluble fiber in legumes, oats, peas, nuts, seeds, psyllium husk, and certain fruit and vegetables. (22) Soluble fibers have been shown to improve cholesterol (6) and blood sugar levels. (20)

Insoluble fiber

This is the type of fiber that does not dissolve in water. It provides bulk and softens stools, helping promote digestive regularity. (12) You’ll find insoluble fiber in wheat bran, whole grains, and certain vegetables. (22)

What is the role of fiber in our diet?

Even though we don’t digest fiber, it still plays an important role in our digestion. Fiber is probably best known for helping to relieve constipation. And research confirms what we know intuitively—fiber does make you more regular. (27)

But new research is beginning to reveal that fiber has more varied—and positive—health effects.

We now know that fiber has more far-reaching health effects, lowering the risk of several diseases—and even the risk of dying from any cause. (28) Research also suggests that low fiber intake, common in Western diet patterns, may be associated with a greater risk of inflammation and susceptibility to pathogens. (23)

Certain types of fiber, known as prebiotics, play an important role in overall health by acting as a source of fuel for the beneficial microbes in the digestive system. These microbes—known collectively as the microbiome—play a role in various body functions, including digestion, immunity, metabolism, and neurological function. (23)

Health benefits of fiber

The research is clear and abundant—fiber is good for you. In fact, a database maintained by the International Life Science Institute contains over 1,000 published manuscripts on the health effects of fiber. (10)

Here are just a few areas of health that may benefit from increased fiber in your diet:

  • Digestive health
  • Heart health
  • Metabolic health (18)

Fiber for digestive health

As we’ve noted, fiber plays an important role in digestive health. But it doesn’t just relieve constipation. It can also help with loose stools by absorbing water from the stool and making it bulkier.

Besides, high-fiber diets can help lower the risk of colon problems, including diverticular disease and hemorrhoids. (4)(8)

Fiber for heart health

A diet that’s fueled by ultra-processed foods—which are notoriously low in fiber—is a recipe for cardiovascular disease risk. (19) A high-fiber diet, on the other hand, has been shown to protect the heart. (24)

One of the ways that fiber—especially soluble fiber—helps heart health is by lowering cholesterol. (2) Fiber may also lower blood pressure and curb inflammation. (1)(16)

woman looking at phone with smoothie in hand in workout clothing

Studies show that fiber supplements help you feel fuller and might be able to help with weight loss too.

Fiber for weight loss

Another way that fiber can help your overall health is by making it easier to maintain a healthy weight. Since fiber is bulky but low in calories, it can help you feel fuller for longer—and help you eat fewer calories. (11)

Research shows that if you’re trying to lose weight, the amount of fiber you eat is directly linked to your chances of success. (13)

Fiber and blood sugar management

Blood sugar issues are a major health concern worldwide. In fact, experts expect that there will be more than 550 million cases of diabetes in the world by 2030. (26) Diet is a major factor involved in the development of type 2 diabetes—the most common form of the condition. (25)

One reliable way to reduce diabetes risk is to increase fiber intake. (25) Fiber can also help people keep their diabetes in check by slowing sugar absorption and keeping blood sugar levels steady. (12)

The microbiome may play a role here as well. Research has shown that certain microbes in the digestive tract produce short-chain fatty acids (SCFAs). Butyrate, one type of SCFA, is associated with improved regulation of glucose. Dietary components such as fiber may benefit gut microbiota composition and, as a result, influence the production of SCFAs and an individual’s glucose response. (23)

Fiber for metabolic syndrome

Metabolic syndrome—also sometimes referred to as Syndrome X or insulin resistance syndrome—is diagnosed when you have at least three of these related risk factors:

Metabolic syndrome increases your likelihood of developing several other conditions—including diabetes, heart disease, and stroke—so addressing it as early as possible is very important. (15)

One way to do that is by increasing fiber intake. Which makes sense, since fiber intake has been shown to improve weight, cholesterol levels, blood pressure, and blood sugar regulation—all components of metabolic syndrome. (3)

Fiber can even protect against not-so-great diets

In one study, researchers gave the insoluble fiber inulin to mice who were eating unhealthy, high-fat, low-fiber diets. The diet had caused the mice to gain weight and develop metabolic syndrome. Adding inulin to their diet seemed to protect them against some of the negative effects of the unhealthy diet including the increased risk of metabolic syndrome. (29)

The researchers concluded that, in mice, fermentable fiber intake may protect against metabolic syndrome by feeding microbiota. (29) While these findings can’t be extrapolated to humans with metabolic syndrome, the results suggest that fiber’s effects on intestinal microbiota may benefit metabolic health.

How much fiber do you need in your diet?

Adequate intake of fiber varies based on age and gender. The following table outlines recommended daily intake of dietary fiber by population. (14)

How much fiber you need depends on your gender, age, and stage in life.

How to get more fiber in your diet

Most Americans are not getting as much fiber as they need. (7) If you want to increase fiber in your diet, the best thing you can do is increase the number of plants you eat. Add more fruits, vegetables, legumes, nuts, whole grains, and seeds to your diet, and you’ll naturally get closer to the recommended intake.

Variety is important too since different foods contain different types of fiber, and they’re all important in maintaining overall health. Plus, the microbiome thrives on variety! (9)

High-fiber foods

Fiber is naturally found in high amounts in various plant-based foods, including:

  • Navy beans
  • White beans
  • Adzuki beans
  • Split peas
  • Chickpeas
  • Lentils
  • Artichokes
  • Pears
  • Pumpkin seeds
  • Avocado
  • Apples
  • Chia seeds
  • Collard greens
  • Almonds (21)

The bottom line

Adding a variety of fibers to your diet is one of the most effective ways of improving your overall health. It’s key to a healthy heart, weight loss, blood sugar control, and more.

If you’re ready to start adding more fiber to your diet, be sure to take it slowly so you don’t experience gas, bloating, or intestinal discomfort. Add some extra plant foods to your diet, and be sure to increase your water intake at the same time. Over time you’ll reap the benefits of a high-fiber diet, all while adding more flavor and variety to your plate!

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