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What makes the Best Grain Free Dog Food?

For many pet owners finding the best dry food for your canine companion can be a daunting task. Whilst many advocate the use of a grain free dog food as an ethical and nutritious solution, what truly makes the best grain free dog food? More importantly, what exactly is a grain free food?

An alternative source

Grain free foods are simply foods that use an alternative starch source rather than starch from grain. Starch is a critical component in the manufacture of a dry pet food as the starch is used to provide the crunch. All high quality dry pet foods are cooked by the extrusion technique, a high temperature and pressure cooking system which is incredibly quick. In fact, extrusion cooking is not only the quickest known method of cooking, but a cooking process that does the least amount of damage to heat sensitive nutrients.

During the cooking process, the starch component of the food mix melts and undergoes a transformation called gelatinisation.

1. The process

This is the same process that occurs when making gravy or a white sauce

Once the starch reaches a critical temperature, the structure of the starch changes and it becomes water soluble, thus thickening the sauce or gravy. Gelatinisation of the starch is important in pet food manufacturing for two reasons.

  1. The gelatinisation process <numbered list>
    Firstly, the molten starch acts as a glue to bind all the ingredients together, and once it cools and solidifies, provides the trade mark crunch that is so useful for cleaning teeth.
  2. The pre-digestion phase
    Second, whilst undergoing the gelatinisation process, starch has the ability to combine with other nutrients to provide nutrient complexes within the food. This process can best be described as a “pre-digestion” process which aids the absorption of nutrients once the dog has eaten the food.

In traditional dry pet foods, the starch is provided by the grain that is used; typically rice, corn, wheat, barley, oats and sorghum. In grain free pet foods, the starch source is typically potato, tapioca (also known as cassava flour or arrowroot), or from pulses such as peas, beans and lentils. So…

2. The Benefits

What are the benefits from feeding the best grain free dog food, compared with feeding an equivalent grain based dry food?

Quite surprisingly, the simple answer is there are very few if any, benefits to be gained. True, some dogs have an allergy to gluten such as that found in wheat, barley and rye, but the incidence of allergy responses in dogs to these forms of gluten are extremely low.

“In one landmark study where 278 dogs with proven allergies were analysed, only 42 of the affected dogs, or 15% of the group, were found to have an allergy to gluten.”
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The balance of the group was allergic to a variety of ingredients including beef, dairy, chicken, egg, lamb, soy, pork, and fish, none of which contain gluten. Furthermore, it is only the gluten that is found in wheat, barley and rye that is responsible for gluten allergies.

  • Brown rice
  • Sorghum
  • Corn
  • Oats <bullet list>

Whilst containing different types of gluten, are considered safe for both gluten intolerant dogs as well as people who suffer from coeliac disease. Conversely, white rice does not contain any gluten as the gluten is removed during the milling process which changes brown rice to white rice.

The major confusing issue here is that whilst many dogs in the wider community actually exhibit sensitivity symptoms, primarily as gut or skin sensitivities, the overwhelming majority (estimated to be between 90 and 95% of all sensitivity issues in dogs) are as a result of poor diet design, not grain as such.

These sensitivities should not be considered allergies such as the response found in dogs with an inherent allergy to gluten. Other than this, there is very little difference between the two types of food, provided of course we are comparing like with like.

There are many poorly designed grain based foods available around the world, but by the same token there are many poorly designed grain free foods as well.

Does this mean the best grain free dog food is just as likely to produce sensitivity issues as grain based foods?

As is often the case in nutrition…

3. Nutritional Requirement

The answer is not quite as simple as “yes or no”

As mentioned above, the vast bulk of sensitivity issues afflicting our canine companions is to do with poor diet design rather than the exclusion of grain.

For a grain free dog food to be the best grain free dog food requires the choice of ingredients to be appropriate for the dog, and those ingredients selected must be contained in the food in the correct levels or ratios to support the gut microbiome.

The gut microbiome is a collection of around 1000 different species of bacteria, viruses and fungi, and their total population exceeds billions. These microorganisms inhabit the gut of the dog and provide essential services to digestion, including the production of some nutrients, the absorption of nutrients into the bloodstream, plus the related effects on both the physical and mental wellbeing of the host dog.

In selecting the ingredients to be used in the food, it is essential to remember that canine nutrition is not the same as human nutrition, and…

4. Inappropriate Ingredients

Just because an ingredient is labelled as a super food in human terms, doesn’t mean it is necessarily good for your dog.

It is the use of inappropriate ingredients that has caused so much anguish for some owners whose beloved pets, after having eaten grain free food, have been found to suffer from dilated cardiomyopathy (DCM).

DCM is a condition whereby the heart becomes enlarged and weak, resulting in a dog with extremely poor circulation that results in shortness of breath, vomiting, lethargy and in the worst-case scenario death. DCM is just one of the unintended consequences of poor diet design, and to be fair is not just confined to grain free foods.

Research in the Cummings Veterinary Centre at Tufts University has resulted in the understanding that DCM is the result of what they term “BEG diets”; boutique manufacturers with little or no scientific background, exotic ingredients that are biological inappropriate, and or grain free foods.

The simple answer to the problem is to ensure the ingredients used are not only biologically appropriate, but are combined in the correct ratios so as to meet the Functional Nutrition requirement of the dog. At the same time, it is essential these ingredients also supply the correct balance of essential nutrients that are required to meet the Genetic Nutritional requirements as well. It should also be said that dogs suffering from DCM do make a full recovery once their diet is changed to a correctly formulated food.

5. What to Include

So, what ingredients should be included in the food if it is to be the best grain free dog food?

This is possibly the most contentious question of all in that there is really no such thing as a poor or bad ingredient, unless of course the ingredient is toxic. The determining factor as to the value of the ingredient is the actual quantity or percentage of the ingredient that can be safely incorporated in the food. The actual amount that is included in the food must be in relation to the quantity and quality of the nutrients that that ingredient supplies.

The other determining factor in selecting the correct ingredients is based on the requirement of the dog’s microbiome population. As mentioned earlier, the microbiome consists of a billion or more bacteria, fungi and viruses, all of which exist in a state of “competitive exclusion”. In other words, the balance of microorganisms is maintained by ensuring each has an equal chance in life when living in what can only be described as a hostile environment. When the ingredient selection is inappropriate, certain species will be well catered for, whilst others will starve, and their population will decline. This then alters the balance of the microbiota by allowing certain species to take control, and once this happens, gut harmony breaks down.

It must be remembered the balance of species making up the microbiome population and the subsequent symbiotic relationship between the dog and these bugs is one that has developed over thousands of years. The modern domestic canine’s evolutionary path separated from the wolf some 15,000 years ago, and throughout all of those years the dog and the gut bugs have evolved to form this current day perfect partnership. Neither can survive without the other.

Unfortunately, a build-up of certain microorganisms, or a lessening of microorganism diversity, can cause a breakdown of the mucus barrier that protects the lining of the gut wall. Once this occurs the gut wall becomes irritated and inflamed which causes the immune system to fire up to battle the attack on that part of the body. From this point on it is a one-way slide to issues of sensitivity (be they gut or skin-based problems), or other more bewildering unintended consequences such as the DCM that was discussed earlier.

Consequently, for the food to be the best grain free food possible, certain basic classes of ingredients must be included in the food in the correct proportions. In an overall context, the majority protein sources should be animal protein (meat or fish) and this would make up approximately 60% of the total food. Vegetables should account for around 35% of the food whilst the balance comprises added vitamins, minerals and dietary balancers necessary to round out the diet.

One of the most common mistakes in attempting to produce a quality grain free food is to include too many legumes in an effort to provide a sufficient quantity of carbohydrate (or starch) to produce the trademark crunch we discussed earlier. Common sources of starch often found in grain free foods are from legumes such as peas and beans. Unfortunately, some foods are based strongly on legumes, and these legumes can contribute high levels of phytoestrogen and other endocrine disrupters. These are suspected in some quarters of leading to fertility issues in breeding bitches. But once again, this only applies to food where the ingredient selection and resultant ingredient ratios fail to meet either or both the dog’s Functional and Genetic nutritional requirements.

A further consideration regarding the ingredients used in making the best grain free dog food centres around the type and quality of the carbohydrate source. As mentioned previously, starchy additives such as potato or root starches from tapioca, arrowroot and cassava are commonly used, as too are the carbohydrates that are supplied from legumes. But starch is not only an inflammatory ingredient, but a contributor to cancer. Cancer cells require carbohydrate to proliferate and current research has shown cancer can be controlled, if not eliminated, by removing the carbohydrate from the diet.

To Conclude:

To summarise and hopefully make some sense of the foregoing, the best grain free food should have the following inclusions and characteristics:

Animal protein

Animal protein must form the major part of the food. Dogs have a well-defined ability to eat and thrive on animal protein sources and these sources must constitute a large portion of the finished meal. Animal proteins are also rich sources of the essential amino acid methionine which is the major contributor of sulphur for the dog. Apart from all the other applications that derive from methionine, the sulphur it contributes plays a critical role in maintaining the correct acid level within the animal.


Vegetables should be added in moderate amounts so as to supply vitamins and minerals necessary for a balanced diet. Remember, our pets are what are termed “captive fed”, which means they have little or no control over what they eat, so if the food we provide is not correctly balanced then a state of malnutrition must result. Additionally, most vegetables are what we call “base forming”. This means these components tend to raise the pH level of the body which in turn raises the pH level of the urine. High pH urine is the major cause of kidney and bladder stones, so it can be seen that keeping the body pH level at the correct level is of vital importance.

Carbohydrate levels

The carbohydrate level needs to be kept to a minimum. Sure, some is required to hold the food together, but that is all that should be included. The last thing any of us or our pets need is more inflammation in the body, or heaven forbid, cancer.

Ingredient selection

An ingredient selection that is biologically appropriate for the dog. It is this area of food formulating, and in particular in relation to the BEG diets mentioned earlier, that many of the unintended consequences that bedevil our canine companions result. High fibre “health foods”, large quantities of fruit, and ingredients contributing excessive levels of omega 6 fatty acids should be avoided at all cost. All have a detrimental effect on the wellbeing of the dog.


But the over-arching consideration must always be balance. The balance of the individual ingredients to one another, plus the balance of the underlying essential nutrients that those ingredients contribute to the food. It is only when the Functional nutritional requirements together with the Genetic nutritional requirements are met in total that we can truly say that the food can be classified as the best grain free dog food.

We trust you have enjoyed this article. Should you wish to read more articles relating to the nutritional health and wellbeing of dogs, please visit the LifeWise web site at and either check out the blog section for a variety of topics and information. You may also ask questions or make comment using using one of the response forms at the end of each article.

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