You’ve probably heard it before- “my dog is on a great diet, lots of protein and grain free”. But what does “grain free” actually mean, and is it associated with better quality food? Why are people choosing to purchase grain free diets for their dogs, and what are the risks? There has been concern over them causing heart issues – has that been disproven now?

What does grain free mean?

Dietary grains refer to carbohydrates like rice, corn, barley, wheat or oats. When a food is advertised as “grain free” it means that none of these ingredients have been added to the food and have been replaced by something else, often potatoes or pulses such as lentils. This is not the same as gluten free, where grains containing the protein gluten have been removed, but there may be other grains in the recipe. 

Does my dog need grain?

Contrary to popular belief, it is the consensus that dogs are in fact omnivores, not carnivores. This means their anatomy and physiology is built to digest some carbohydrates, as well as meat. Grains contain antioxidants, as well as vitamins and minerals that help to create a balanced diet for your dog. Grains are made up of starch, which can also help to contribute towards good gut health.

Why are there so many grain free diets available if grain is so great?

Like so many other things, grain free has become popular among dog owners due to misinformation and good marketing. This is partly because of the misconception that dogs are carnivorous and don’t need grains; meaning that grains are considered just a “filler” to make dog food more cheaply. The other misconception is that grains are a common allergy in dogs. And that they are unsuitable for dogs with itching or sensitive stomachs. Again, this is a misconception, with less than 1% of dogs having a true grain allergy. In fact, chicken, beef and dairy are the most common allergies in dogs. So, unless your dog is one of the few that has a true grain allergy, there is no evidence for a grain free diet being beneficial.

What are the risks with grain free foods?

Some recent research has highlighted a possible, but considerable danger with grain free diets. A study of young, healthy dogs investigated this, one half on a “traditional” diet (including grain) and the other half on a “non- traditional” diet (excluding grain and including potatoes or pulses as a main ingredient). It was found that the dogs on the non- traditional diet had poorer heart function and larger left ventricular volumes (one of the heart chambers) when compared to the dogs on the traditional diet.

What can be taken from this is that there is evidence that feeding a grain free diet to dogs could put these dogs at higher risk of developing diet associated dilated cardiomyopathy (DCM). We have seen reports of clinical disease resulting from some of these diets before, but this new study is the first to demonstrate measurable changes in the heart function of dogs who have not (yet) developed clinical disease, and to solidly link it to the grain-free diet.

What is DCM?

DCM is a disease of the heart which is seen most frequently in large breed dogs, particularly in breeds such as the Doberman. It is characterised by a large left ventricle, which becomes larger as the muscle wall becomes thinner and weaker as the disease progresses, leading eventually to heart failure. Many things as well as being a pre- disposed breed can lead to DCM, such as arrhythmias, metabolic diseases and diet.

To summarise, it is important to consider whether a grain free diet is the right choice for your dog. Speak to your vet if you are unsure, but there are possible risks of choosing to cut out the grain altogether. Consider instead looking for a high quality grain inclusive food, can help you to compare dog foods using key ingredients, health needs and prices.

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