Types of Fiber

Fats, proteins, and carbohydrates are macronutrients the body breaks down and absorbs for energy. Dietary fiber is unique in that the body cannot digest or absorb it. There are two types of fiber—soluble and insoluble fiber. Some foods contain both soluble and insoluble fibers. 

Soluble

Soluble fiber dissolves in water. When dissolved in water, soluble fiber creates a gel-like consistency that improves the shape, size, and texture of stool, helping to ease the passing of bowel movements. Soluble fiber may also support gut health by increasing the beneficial bacteria in the intestines.1 

These foods are excellent sources of soluble fiber: 

• Oats
• Apples
• Carrots
• Citrus fruits
• Psyllium
• Beans
• Apricots
• Ground Flax Seeds
• Sunflower Seeds
• Sweet Potatoes
• Avocados

Insoluble

Insoluble fiber does not dissolve in water. This type of fiber can accelerate gut transit time, easing the movement of stool through your digestive tract.2

The following foods are rich in insoluble fiber: 

• Apples, with skin
• Pears, with skin
• Beans and lentils
• Berries
• Whole-wheat flour
• Wheat bran
• Cauliflower
• Potatoes
• Spinach 
• Okra
• Dried apricots, raisins, prunes, and dates
• Almonds
• Walnuts
• Popcorn

What Are the Health Benefits of Fiber? 

Fiber has many health benefits! Some of the health benefits of fiber include:3

• Helps prevent and treat constipation 
• Helps slow down the absorption of carbohydrates and sugar, which helps maintain healthy blood sugar levels 
• May help reduce the risk of colorectal cancer 
• May help manage weight by improving satiety and helping you feel fuller longer 
• May reduce the risk of diverticulitis 
• Increase microbial diversity in the gut, supporting overall gut health 

How Much Fiber Should I Eat Per Day? 

The American Heart Association recommends eating 25 to 35 grams of fiber daily from food sources, not supplements. However, because the Standard American Diet is often high in low-fiber and processed foods, the average American adult does not meet this recommendation, consuming an average of only 15 grams of fiber daily.