What is fibre, and what does it do?

We’re all familiar with the breakfast cereal adverts that adorn our televisions with happy, healthy and active bodies enjoying a delicious breakfast boasting the benefits of fibre, but what is it, and what are the benefits particularly for our dogs?

Fibre is a carbohydrate that cannot be fully broken down during the digestive process. From a ‘back-end’ perspective there are often questions around the value of these inclusions to the canine diet when pet owners will regularly note ingredients looking the same having gone through the digestive tract as they did before. While this may be a fair observation, the function and benefit of dietary fibre cannot be underestimated, and dietary fibre forms a very valuable element to a dog’s diet.

Fibre travels though the digestive tract undigested, but once it reaches the large intestine, or the colon, this is where things get interesting. The natural flora in the gut starts to ferment the soluble fibre which helps to produce short chain fatty acids, which then becomes an energy source at a cellular level for the gut.

Soluble Fibre

Soluble fibre draws water into the large intestine forming a gel-like substance and ‘feeds’ good gut flora, forming short chain fatty acids. This helps with blood glucose and cholesterol regulation, as well as supporting the immune system.

Insoluble Fibre

Insoluble fibre has numerous functional benefits around the mechanics of the formation and consistency of faeces and moderates the speed at which faecal matter passes through the digestive tract to ensure appropriate nutrient absorption. Insoluble fibre may also be seen as nature’s little cleaning brush for your gut

Insoluble fibre sources are particularly beneficial to ensure optimal faecal consistency to aid in naturally emptying anal glands.

Some Examples Fibre Sources:

  • Vegetables & fruit
  • Wheat bran.
  • Seaweed
  • Whole grains such as barley, rice and oats
  • Prebiotics
  • Pysllium husk/chia and flax.
  • Beet pulp.
  • Chicory root
  • Inulin
  • Alfalfa
  • Gums (i.e. agar agar, guar, xanthan, cellulose).
  • Pectin from fruit that give jams the gel-like texture.

Dietary Fibre & Weight Control

Dietary fibre is very useful for controlling weight as it contributes to ‘’satiety’’, that feeling fuller for longer. Many dog foods specifically targeting weight loss or weight control will be formulated based on increased fibre and reduced energy.

What about too much or too little?

Like all good things in life, balance is key. A diet with insufficient fibre will likely lead to poor quality faeces such as diarrhoea or constipation. Equally a diet in excess of fibre is likely to produce large, bulky faecal outputs, long term poor skin and coat condition, and weight loss.

The immune system, gut and happy tails.

It’s a fascinating topic recognising the microbiome in the gut directly affects the immune system. In fact, there’s reports to suggest that 70% of our immune system resides in the gut. In addition to this, the gut-brain axis concept links a healthy gut with a healthy mind as serotonin (the mood-modulating chemical transmitters) is largely produced in the intestinal tract. It’s likely the adage ‘’you are what you eat’’ comes from this very concept. This further supports the incredible value of supporting a healthy gastro-intestinal tract through appropriate diet.

The Role of the Canine Gut Microbiome and Metabolome in Health and Gastrointestinal Disease – PMC (nih.gov)

Best Sources Of Fiber For Dogs – Dogs Naturally (dogsnaturallymagazine.com)


Prebiotic diet – FAQs – Department of Gastroenterology (monash.edu)