CARBOHYDRATES IN DOG FOOD: ALL YOU NEED TO KNOW

What are Carbohydrates?

“Fast carbs” and “slow carbs”: the terms may be outdated, but they'll most certainly mean something to you. Carbohydrate is a synonym of the word saccharide, which comes from the Greek word σάκχαρον (sákkharon), meaning "sugar". The saccharide group includes sugars, starch, and cellulose, and is divided into four chemical groups: monosaccharides, disaccharides, oligosaccharides, and polysaccharides.

Monosaccharides and disaccharides, the smallest carbohydrates, are commonly referred to as sugars. One of these sugars, glucose, is a form of energy that can be used quickly by the body, i.e. a "fast carb". A vital energy source needed by all the cells and organs of our bodies, glucose can also be obtained from proteins through "gluconeogenesis" (in smaller doses).

Polysaccharides (e.g. starch) are a group of carbohydrates which contain thousands of glucose molecules linked together. These serve to store energy for slow release, i.e. "slow carbs".

There are very few carbohydrates in the animal world, except for lactose (milk sugar), honey, glucose stores in an animal's liver or blood, and a little bit of glycogen in the muscles. On the other hand, plants contain a lot of carbohydrates.

Whether in the form of grains (corn, barley, wheat, oats, rice, etc.), tubers (potatoes, sweet potatoes, etc.), or legumes (peas, lentils, etc.), all dry dog food contains a certain amount of carbohydrates, and rarely less than 20%.

The Different Types of Carbohydrate

There are two kinds of carbohydrates, with each playing a different role.

👉 Digestible Carbohydrates

Digestible carbs, also known as available carbohydrates or net carbs, are found in dry dog food in the form of starch. Starch slowly provides the glucose essential for brain function and most metabolic reactions (vitamin C synthesis, for example). A lack of glucose can cause hypoglycaemic attacks, which forces the brain to shut down so as not to put the body in danger.

👉 Indigestible Carbohydrates

These are dietary fibres that ensure the proper functioning and protection of the digestive tract and the gut flora. These fibres nourish and maintain the microorganisms found in the intestines. Also known as prebiotics, they facilitate good digestion by preventing the growth of bad bacteria and improving the absorption of nutrients.

Carbohydrates in Dog Food

In dry dog food, in particular, carbohydrates are used for two things:

• to enable extrusion, the manufacturing process used to produce most dry dog food

• to provide rapidly usable energy in the form of starch

Be wary of popular misconceptions: Starch itself is not a bad thing, it provides the glucose essential for the good health of your dog. In fact, it's so important to the survival of the body that natural selection has developed a way for animals to synthesise glucose from protein... to ensure that they don't die during periods when there is no fruit, honey, or other sources of glucose available in the wild.

When we talk about "nonessential" carbohydrates, it certainly doesn't mean they're not important. Human digestion has only evolved through our mastery of fire (to cook starch) and farming. Domestic pets have benefited from this evolution for thousands of years, so why send them back to the Stone Age now?

What is the Correct Level of Carbohydrates in Dog Food?

As with many other things, it's all about balance. There's no need to worry about glucose intake, as we know that our dogs can synthesise this themselves. Likewise, an excess is usually not due to a problem with the quality of the food but rather with feeding behaviour: Food rich in sugar will not cause diabetes, but food rich in sugar given in too large a quantity to an obese animal will certainly contribute.

Indigestible fibres must be provided by your dog’s food. Depending on your dog's activity level and their age, their food should contain between 8 and 16% indigestible fibre to ensure good digestive transit and maintain good intestinal hygiene.

The Different Types of Fibre

They are of two kinds of fibre:

👉 Insoluble Fibre

Indigestible carbohydrates (cellulose) that cannot be fermented and used by bacteria in the large intestine. As such, they encourage good digestive transit and promote intestinal hygiene by stimulating the renewal of the digestive mucosa. Wheat bran is a great source of insoluble fibre, for example.

👉 Soluble Fibre

These are carbohydrates which are not digestible but which can be fermented by bacteria in the large intestine. These fibres nourish and maintain the microorganisms found in the intestines. Also known as prebiotics, they facilitate good digestion by preventing the growth of bad bacteria and improving the absorption of nutrients. Beet pulp, blond psyllium, and oat bran are great sources of soluble fibre.

It's all a Matter of Quantity

As detailed previously, carbohydrates are a valuable source of energy which are very useful for:

• Rapid intake of glucose, the best source of energy for the brain and muscles: Glucose is so vital to body function that it is also synthesised from protein (in smaller quantities)

• Stimulating the digestive system (fibre)

• Maintaining the balance of the intestinal flora (fibre)

It is unnecessary to increase the amount of starch in your dog’s diet. But it’s just as pointless to wage war on carbohydrates and seek to eliminate them at all costs. Carbotoxicity—the excessive intake of carbohydrates—is much less of an issue than excessive protein intake, in terms of a dog’s health in the medium term. Again, it's all about proportion and balance.

So, How Do I Determine the Level of Carbohydrates in My Dog’s Food?

Please note: You may have to calculate the level of carbohydrates in your dry dog food yourself, as it is often not mentioned on the packet! An excess of carbohydrates can cause digestive problems and more serious pathologies if the diet in question is given long term to an animal with a predisposition or an underlying pathology, such as diabetes, hypertension, obesity, or other "new" ailments linked to the use of foods not suitable for our animals.

The magic formula to calculate the "Nitrogen-Free Extract" or NFE of your dog food is simple: 100 - (% protein + % fat + % cellulose/fibre + % crude ash + % water).

This formula gives an approximate percentage of more or less digestible carbohydrates which contain starch, as well as soluble fibre, hemicellulose, etc. In short, compounds that are difficult to separate and determine properly.

The NFE that we calculate is, therefore, a somewhat vague indication which serves to give us an idea of the percentage of available starch, usually between 1 and 15%. But the quality of dry dog food is not limited to its NFE rate, and therefore its level of carbohydrates!

To "lower" the carbohydrate content of your dog’s dry food diet, feed them high-quality kibble that they tolerate well and add in other foods with high water and meat content, such as high-quality comprehensive wet food, homemade dog food, or even BARF rations. You can also give them some vegetables or fish oil, both healthy additions which ensure good health.

Why is the Level of Carbohydrates Not Mentioned on Dry Dog Food Packets?

There are methods for analysing the starch content of your dry dog food, but indicating this level on the packet is simply not obligatory. Moreover, this rate, whether high or low, is not necessarily an indicator of dangerous food. In reality, it would be more relevant to know the degree of gelatinisation of the starch contained, as this would give us an idea of the “digestible” quantity.

The levels of protein, fat, fibre, etc. indicated (or calculated for carbohydrates) on your dry dog food packet are averages which usually vary by between 1 and 3%, or even more according to the levels permitted by regulations in force. The manufacturer will know the exact minimum and maximum percentages allowed for each type of nutrient contained in their feed, but the brand that markets the products only has to communicate the average or the maximum or minimum value for certain nutrients. Also, don't forget that dry dog food is made from lots of different ingredients on an industrial scale!

In Conclusion

When choosing the ideal food for your dog, take a step back from what you read and consider their diet as a whole. Take into account the quality of the ingredients contained, and all the nutrient levels indicated or calculated... while knowing that a large part of the information (protein quality, amino acid content, degree of starch gelatinisation, etc.) remains unknown to us.