Food & Feeding

What Does Digestibility Actually Mean in Dog Food?

Digestibility describes how much of a food can be broken down and absorbed by the body. A food can look impressive on the label, but what matters nutritionally is how much of its protein, fat, carbohydrate and other nutrients the dog can actually access and use.

Introduction

Dog-food labels tell us what ingredients went into the bag.

They do not tell us exactly how much nutrition the dog will ultimately absorb.

That is where digestibility becomes important.

Digestibility describes the proportion of a food or nutrient that is broken down and absorbed rather than passing through the gastrointestinal tract unused.

Two foods can contain similar amounts of protein, fat or carbohydrate on paper but behave differently once eaten.

The more useful question is therefore not simply:

“What is in the food?”

It is:

“How much of it can the dog actually digest and use?”

Understanding the issue

What is happening?

Digestion begins before nutrients can be absorbed.

Food must first be broken down into smaller components.

Proteins are broken into peptides and amino acids.

Fats are broken into fatty acids and related compounds.

Carbohydrates are broken into smaller sugars or other molecules, depending on their structure.

These smaller components can then be absorbed through the intestinal wall and used by the body.

Anything that is not digested or absorbed earlier in the gastrointestinal tract continues further downstream.

Some of that material may be fermented by microbial communities in the large intestine.

Some may ultimately leave the body in the stool.

This is why digestibility can influence more than nutrition alone.

It can also affect stool volume, stool consistency, gas and the substrates available to the gut microbiome.

Common factors

What can influence it?

Several things can influence how digestible a dog food is.

The ingredient itself

Different protein, fat and carbohydrate sources have different structures and nutritional characteristics.

Processing

Cooking, extrusion and other manufacturing processes can make some nutrients easier to digest, while excessive processing or heat can sometimes alter nutrient quality.

Protein source

Two foods with the same crude protein percentage may provide that protein from very different ingredients with different amino acid profiles and digestibility.

Fibre

Some fibres are poorly digested by the dog but may still be useful because they influence stool formation or microbial fermentation.

Anti-nutritional compounds

Some plant ingredients contain compounds such as phytates, which can bind minerals and influence their availability.

The individual dog

Age, gastrointestinal health, pancreatic function and other biological differences can influence digestion.

The complete formulation

No ingredient should be judged entirely in isolation. The way ingredients are combined matters.

What you may notice

What can you observe?

Owners cannot calculate true digestibility simply by looking at a food bowl.

But there are useful things to notice.

Stool volume

Very large volumes of stool can sometimes indicate that more material is passing through the gastrointestinal tract rather than being absorbed.

Stool quality

Consistently well-formed stools can be one useful sign that a diet suits the dog, although stool appearance alone does not prove excellent digestibility.

Gas

More material reaching the lower gut can mean more substrate is available for microbial fermentation, which may increase wind in some dogs.

Body condition

A dog eating an apparently adequate amount of food should generally be able to maintain appropriate body condition.

Coat condition

Protein, fats, vitamins and minerals all depend on adequate intake, digestion and absorption.

Appetite and feeding amount

Needing unusually large amounts of food to maintain condition can sometimes be worth discussing with your vet or nutrition professional.

The important point is to look at the pattern rather than relying on one sign alone.

Everyday considerations

Do not assume that a food with the highest protein percentage is automatically the most nutritious.

Crude protein tells you how much nitrogen-containing material is present.

It does not tell you the amino acid profile, digestibility or biological value of that protein.

The same principle applies more broadly.

A nutrient has to be present, digestible and absorbable before the body can use it effectively.

That is why food quality should be considered in terms of the complete formulation rather than one impressive number on the packet.

When comparing foods, look at:

the main protein sources
whether the food is complete for the dog's life stage
ingredient quality
how the dog maintains body condition
stool quality
appetite
coat condition
how much food is required to maintain the dog

Digestibility is not the only measure of food quality, but it is an important part of the picture.

For a research example of diet affecting gut measurements, see how different fibres shaped the canine microbiome and metabolome.

When to speak to your vet

Speak to your vet if you are concerned that your dog may not be digesting or absorbing food normally.

Veterinary advice is particularly important if you notice:

unexplained weight loss
difficulty maintaining body condition
persistent loose stools
unusually large stool volumes
repeated vomiting
excessive gas alongside other digestive signs
reduced appetite
a dull coat alongside poor condition
weakness or lethargy

Problems with digestion or nutrient absorption can have many different causes.

Persistent signs should not be managed solely by repeatedly changing foods or adding supplements without understanding the underlying reason.

Where CaniNectar fits

Digestibility sits at the heart of the nutritional rationale behind CaniNectar.

CaniNectar contains enzyme-rich malt extract, or ERME, produced using a patented process designed to preserve naturally occurring digestive enzyme activity.

Its enzyme profile includes protease, lipase, amylase, fructanase, cellulase, xylanase, beta-glucanase and phytase.

These enzymes act on different components of food.

The basic nutritional idea is to support nutrient breakdown earlier in the digestive process, before material reaches the lower gastrointestinal tract.

That matters because improved breakdown upstream can influence both nutrient availability and the amount and type of substrate reaching microbial communities further along the gut.

CaniNectar's field research has reported changes consistent with this digestive rationale, including firmer stools and reduced wind in dogs that began with sub-optimal digestion.

CaniNectar is a complementary feed for healthy dogs and is not intended to treat malabsorption, pancreatic disease or other gastrointestinal conditions.

References

Further reading:

FEDIAF. Nutritional Guidelines for Complete and Complementary Pet Food for Cats and Dogs.

Case LP, Daristotle L, Hayek MG, Raasch MF. Canine and Feline Nutrition: A Resource for Companion Animal Professionals. Mosby Elsevier.

Wernimont SM, Radosevich J, Jackson MI, et al. The Effects of Nutrition on the Gastrointestinal Microbiome of Cats and Dogs: Impact on Health and Disease. Frontiers in Microbiology. 2020;11:1266.

Pilla R, Suchodolski JS. The Role of the Canine Gut Microbiome and Metabolome in Health and Gastrointestinal Disease. Frontiers in Veterinary Science. 2020;6:498.

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