Is There a Problem When It Comes to Grain Free Dog Food?

Updated: Jun 7

There’s a lot of mixed information about grain free dog food out there, so you’re probably confused about what the best choice for your dog is. Grain-free diets (GFDs) were once thought to be the healthier option; however, recent studies suggest there might be a connection between feeding grain free pet food and diet-induced dilated cardiomyopathy (DCM). This blog post is here to help! We will go through a few important points to help you better understand the myths and facts surrounding grain-free diets vs. grain-inclusive diets and how raw feeding fits into that picture.


This Article Explores:



What Does Grain-Free Mean? How Does It Apply To Grain-Free Diets For Dogs?

The term “grain-free” refers to commercially processed diets that do not contain wheat, rice, oats, corn, barley or other grain material. They can be dry, canned or dehydrated. GFDs employ legumes like lentils or chickpeas as a substitute for grain in their formulas. This method of feeding started to gain popularity about 10-15 years ago when it became recognized that dogs and cats can have allergies to cereal grains. Pet food companies jumped on board, using legumes as grain alternatives. Meat and legumes are both high in protein but where meat doesn’t contain starch, legumes do, especially in a heat-processed form.

Is There a Problem When It Comes to Grain Free Dog Food?


What Makes Protein? The 10 Essential Amino Acids For Dogs

Protein is made up of chemical compounds called amino acids (AA’s). Foods that contain protein each have their own unique variance of “essential” and “non-essential” AA’s, according to the American Association of Feed Control Officials (AAFCO). Protein isn’t just protein.


According to AAFCO, There Are 10 Essential Amino Acids for Dogs:

  • Arginine

  • Histidine

  • Isoleucine

  • Leucine

  • Lysine

  • Methionine

  • Phenylalanine

  • Threonine

  • Tryptophan

  • Valine

Non-Essential Amino Acids for Dogs:

  • Alanine

  • Beta-alanine

  • Asparagine

  • Aspartic acid

  • Citrulline

  • Cysteine

  • Glutamic acid

  • Glutamine

  • D-glutamine

  • Ornithine

  • Taurine

  • Hydroxyproline

  • Proline

  • Serine


Not All Amino Acids Are Equal- Canine Amino Acids 101

The 10 essential amino acids need to be present in specific parameters in order to meet the nutritional needs of dogs. Behind the happy, healthy pup you spend time with, there are a lot of metabolic conversions that go on inside their body every day. Essential AAs can be converted into several forms. They are like building blocks and have to be present in the right amounts in order for your dog to get all the right nutrition. You’ll notice that taurine is listed as non-essential for dogs. Taurine is well recognized as an important nutrient for cardiac health. Scientists have established that dogs can make taurine from methionine and another non-essential AA called cysteine.


The Amino Acid Differences Between Meat and Legumes.

Below, you can see the differences in the amino acid profiles of some common meat and plant protein sources used in raw and grain-free pet foods.

*non-essential but cysteine is a precursor for taurine


You can see that meat proteins are significantly higher in AAs across the board compared to legumes. Also note the drastic difference between the cysteine and methionine profiles and why this could be a significant contributing factor to AA deficiencies, mainly taurine deficiency.


What is Taurine? Why Is It Important For Dogs

Taurine is an amino acid that is (as of yet) not recognized as essential for dogs but it is essential for heart health. It’s a key nutrient in helping the body regulate blood pressure. While taurine for dogs isn’t recognized as essential, your dog could become deficient in methionine and cysteine, making taurine conversion impossible. Meat contains the highest known naturally occurring levels of taurine and is also high in methionine and cysteine, making it easy for dogs to regulate their taurine intake. Legumes have a completely different amino acid profile, do not contain taurine and are low in methionine. This is why we are so huge on species-appropriate nutrition. It’s hard to go wrong when you feed them an ancestrally correct diet!



Is Grain Free Dog Food Bad?

Yes and no. While GFDs may temporarily relieve your pet of allergy symptoms, there are a number of pros and cons:


Pros of Grain Free Dog Food

  • Pro: Legumes are cheaper than meat so it can be more cost-effective to produce and to buy than meat.

  • Pro: Plant-based foods are more sustainable that meat.

  • Pro: Pets are less likely to be allergic to legumes than grains and may provide relief for those suffering from grain allergies.

Cons of Grain Free Dog Food

  • Con: If you’re using a grain-free diet to try and reduce starch by cutting out the grains, we have some bad news: highly processed legumes can contain just as much or more starch as highly processed grains. If you’re dealing with an itchy dog with yeast problems, you may be chasing your own tail.

  • Con: Unless legumes are certified organic, they are heavily sprayed with the herbicide glyphosate (AKA RoundUp) which has over 200 peer-reviewed studies listing multiple serious health risks including cancer. Grain free pet foods have been recorded as having the highest glyphosate levels of any pet food on the market.

  • Con: Since legumes and meat both contain protein, pet food companies may use legume protein and reduce the meat protein content. This changes the amino acid profile. It still meets the protein standards but may be lacking in the correct amino acid ratios.

  • Con: If a grain-free diet is lacking in amino acids methionine and cysteine it may leave a dog unable to produce enough taurine to maintain a healthy heart. You may have noticed in the table above that methionine and cysteine levels in legumes are significantly lower than in meat. Reduced access to methionine and cysteine may result in taurine deficiency, a major contributing factor to canine dilated cardiomyopathy (DCM) - keep reading for more on DCM.

  • Con: Some grain-free pet food companies have started adding taurine to their diets to cover any deficiencies that might occur with legumes. However, there’s one more factor in amino acid imbalance when it comes to grain-free dog food: lectins. Lectins are naturally occurring plant proteins found in legumes that can block the uptake of methionine and cysteine in dogs. Because pet food manufacturers can displace meat protein with legume protein, lectin levels are higher in grain-free diets and might compound the complications of amino acid imbalance/deficiency.

  • The FDA is still investigating... Read more about diet-induced canine DCM here.