The Dog Food Project
In moments of joy, all of us wished we possessed, a tail we could wag. - W. H. Auden
A better food makes a big difference!

Main Page About the Author What Readers say Dog Discussions Forum
Commercial Dry Foods
Introduction Label Information 101 Identifying better products Ingredients to avoid Product List
Specific Product Groups
Organic Dog Food Grain Free Dog Food Vegetarian & Vegan Dog Food
Meat vs. Meat MealNew! Choosing the right food Feeding Puppies Feeding Senior Dogs Canine Obesity Is too much protein harmful? Grading kibble - easily? "Five Star Foods"
Other Diet Topics
Questions on Diet Myths about Feeding The Yuck Factor Where the money goes Natural Supplementation Menadione (Vitamin K3) Nutrient Requirements Links & Resources
Nutrition Primer
Nutrient Overview Water Protein Fat Carbohydrates Fiber Vitamins Minerals Essential Fatty Acids Probiotics

Get Firefox!

Dietary fiber

The term "fiber" refers mostly to complex carbohydrates which are not digested by the endogenous enzymes in the small intestine of dogs (digestion and absorption increases if these enzymes are supplemented). Some fibers are partially digested by beneficial bacteria present in the healthy large intestine. Cellulose, hemicellulose and pectin are three major carbohydrate based components of fiber, the fourth, lignin, is the only one that is not carbohydrate based. The properties of fiber are classified as follows:

Solubility: the ability of fiber to hold water and form a gel-like substance. Highly soluble fibers can hold a lot of water, decrease gastrointestinal transport and slow nutrient absobtion. Insoluble fibers do not hold much water and increase gastric emptying.

Fermentability: the extent of bacterial digestion in the large intestine, which results in various end products that can in turn be metabolized by the dog's body.


  • Cellulose: low solubility and fermentability
  • Beet pulp: low solubility, moderate fermentability
  • Pectin: low solubility, high fermentability
  • Guar gum: high solubility and fermentability
  • Gum arabic, Xanthan gum: high solubility, moderate fermentability
  • Locust bean gum: high solubility, low fermentability

Herbivores (especially ruminants) with their elaborate digestive system are able to draw a high amount of energy from short chain fatty acids (SCFAs) produced by bacterial fermentation of fiber. Dogs with their short and simple digestive tract do not have this ability, but still benefit in a different way - the enterocytes and colonocytes lining the gastrointestinal walls are active cells with a very high turnover rate that utilize short chain fatty acids as a significant energy source.

A moderate amount of fiber in the diet aids in the transport of the stomach contents through the intestines and promotes regular elimination. Excessive amounts often cause loose stools, gas and increased stool volume and frequency. High fiber diets are often used for management of diabetes mellitus and/or obesity in dogs.