Fiber: the importance of an often overlooked nutrient

We’ve all heard of fiber and the fact that it’s something you should include in your dog’s diet.

But what is exactly is it? And why should you endeavour to ensure your dog is eating some fiber as part of a healthy, balanced diet?

Fiber – one word, different things

Fiber is a type of carbohydrate that your dog’s body cannot break down. Whereas other carbohydrates are broken down into sugar molecules, dogs lack the digestive enzymes required to break fiber down. This means any fiber you dog consumes passes through their body undigested.

Fiber can be classified in a variety of ways, including based on the rate at which it’s fermented or how viscous it is.

It can also be classified as dietary fiber – that is, fiber found naturally in foods – or functional fiber – fiber that’s extracted from whole food subsequently added to processed food.

However the most common way that fiber is classified is by its solubility in water – that is whether or not it dissolves in water. This post will focus on fiber with regards to solubility.

Soluble fiber

Soluble fiber can dissolve in water – it mixes with water in the gut to form a gel-like substance. It is known to promote the growth of ‘good’ bacteria within the gut and digestive tract and it can reduce spikes in blood sugar levels. Certain microbes found in the large intestine are able to break down fiber to a varying degree. This bacterial fermentation produces fatty acids that act as an important energy source for the epithelial cells lining your dogs gastrointestinal tract.

Sources of soluble fiber to consider including in your dog’s diet include:

  • Oats
  • Beans
  • Sweet potato
  • Apples

Insoluble fiber

As the name suggests, insoluble fiber is the opposite of soluble fiber – it does not dissolve in water. Instead, insoluble fiber passes through the digestive system pretty much intact. Its main function is to act as a bulking agent and regulate transit time to allow sufficient absorption of nutrients but not cause constipation.
Sources of insoluble fiber to consider including in your dog’s diet include:

  • Whole grains
  • Flaxseeds
  • Sweet potato
  • Skin of fruits and vegetables

The health benefits of fiber

While not necessarily considered essential, there are a lot of health benefits that come with including fiber in your dog’s diet.

For example, while it may sound contradictory, fiber is known to play a role in treating both diarrhoea and constipation.

Soluble fiber can help alleviate the symptoms of some types of large bowel diarrhoea, which include the presence of blood or mucus in your dog’s stool, or your dog having to frequently ‘go’ but only producing a small amount of stool at any given time.

Because it can absorb water, soluble fiber can help dog’s with large bowel diarrhoea form stools and better control their bowel movements.

Large bowel diarrhoea isn’t the same as small bowel diarrhoea, meaning they shouldn’t be treated the same. Symptoms of small bowel diarrhoea include infrequent emissions of large amounts of loose stools, and it tends to be best treated with a low-fiber, highly digestible diet.

On the other hand, constipation can be prevented and treated with both soluble and insoluble fiber. Insoluble fiber doesn’t absorb water, meaning it can speed up the passage of food and waste through the digestive tract, while soluble fiber keeps water in stools making them softer and easier to pass through your dog’s digestive tract.

Care should be taken with insoluble fiber because too much of it can act as a natural laxative. And if your dog experiences diarrhoea or constipation for a long period of time, speak to your vet.

Fiber is also known to play a role in appetite and weight management. As a food it has very few calories, meaning dogs can consume a lot of it without gaining a lot of weight. At the same time it’s very filling, meaning dog’s tend to feel fuller for longer and in turn, eat less. Essentially, it can create a feeling of satisfaction and fullness without adding extra calories. In this way it can both prevent dogs becoming obese and it can help dogs who need it to lose weight.

Diets rich in fiber are also thought to help reduce the risk of diabetes by playing a role in controlling blood sugar levels.

Don’t overlook it

While fiber is often included in commercial diets, for those who feed their dogs a home-cooked meal, the importance of fiber shouldn’t be overlooked.

Foods that are rich in fiber also have other health benefits too, so every effort should be made to include them in your dog’s diet.

And while there are different types of fiber, unlike fats, neither is necessarily better than the other. Both soluble and insoluble fiber are beneficial to your dog’s health, meaning both should be incorporated into a dog’s diet.