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5 Surprising Ingredients That Cause Cat And Dog Stomach Upset tips

5 Surprising Ingredients That Cause Cat And Dog Stomach Upset

Does your pet suffer from itchy skin, chronic ear infections, excessive gas, loose stools, vomiting, or just not eating? It may be time to take a look at their diet.

As pet parents, we always want what’s best for our furry friends. That includes giving them a well balanced diet. Picking out the right recipe for your dog or cat can be tough: even the most seemingly natural pet foods can be full of filler ingredients and digestive irritants. That’s why it’s important to know right from the start what foods to look out for. 

Here are 5 common ingredients in cat and dog food that have been shown to cause digestive problems:


1. Starches (Green peas, beet pulp, potato, sweet potato, etc.)

Sometimes, we make the error of assuming that, if an ingredient is good for us, it must be good for our pets. The reality is, dogs and cats are natural carnivores that thrive on a high protein diet. While us humans can benefit from a variety of ingredients in our diet like green peas and sweet potatoes, the same cannot be said for pets. Starches are common ingredients in pet food - but they’re not doing our pets any favors. These are filler ingredients that keep manufacturing costs down. They provide no health benefits to dogs and cats, and can often be digestive irritants.

Pet food companies may claim that peas, corn, and other similar ingredients are good for your pet, but they actually may be the culprit of your pets digestive problems, or even allergies. 

If your pet is suffering from digestive upset, or food allergies, be sure to check their food for the following ingredients that could be causing these issues:

  • Green Peas
  • Beet Pulp
  • Potato
  • Corn
  • Barley
  • Wheat

When picking out the right pet food for your pet, a high-quality, grain-free pet food is the safest choice. You can read more about picking the best grain-free food for dogs, here.


2. Meat by-products and grain by-products

Take a look at your pet food ingredients list. Do you see a protein source that ends in “by product?” A significant number of pet food brands choose to use these products, rather than the true protein (i.e. meat by product instead of a meat source itself) to keep costs low while maintaining a higher protein and calorie content. Look for animal proteins in the first three ingredients for the most beneficial source of protein and essential amino acids.

When the meat source is unspecified, it truly is unknown what your pet is consuming. This can be problematic when dealing with a food allergy. If your dog or cat is experiencing food-related allergies, be conscientious of what protein source is in their food to determine if that’s the cause, and if there’s a better alternative for them. 


3. Soy Products (soybean meal, textured vegetable protein/TVP, isolated soy protein, etc.)

In recent years, soy products have been used more and more frequently in pet foods, including prescription diets. Soybean meal is the most common, and is used often because it’s a cheap source of protein. Many manufacturers often state that soy is a good alternative protein source for pets with food allergies to meats like chicken or turkey. 

In spite of their prevalence, soy products can actually be an allergen as well. For dogs and cats alike, it can cause allergic reactions such as skin rashes, itching, and hair loss in addition to stomach upset. This is an increasing trend among genetically modified products. 

Additionally, studies have recently emerged that have linked soy to gastric dilation volvulus (GDV), or bloating. GDV is a serious condition, where air accumulates in the stomach, causing the stomach to twist and restricting blood flow throughout an animal’s body. If not treated immediately, the risk of fatality is high. While the causes of GDV, as well as preventative steps are still being researched, there are a few facts we know. According to the American Kennel Club, “foods containing soybean meal or having oils or fats in the first four ingredients increase the risk [of GDV] by fourfold.”

Although bloating is most common in large breed dogs, it can develop in small dogs and even cats. If you’re concerned that your pet is experiencing bloating, make sure to contact your veterinarian immediately.


4. Chemically altered proteins (hydrolyzed chicken, hydrolyzed soy protein isolate, etc.)

Hydrolyzed proteins are typically prescribed by veterinarians in an effort to minimize the food allergies pets may experience. It is also prescribed to dogs and cats that have been diagnosed with Irritable Bowel Syndrome (IBS). These foods are formulated through hydrolysis, a process in which water chemically breaks down protein into pieces that are so small, the immune system no longer reacts to them. So if a cat or dog has allergies to chicken, they may be given hydrolyzed chicken instead to see if that eliminates the reaction while ensuring they’re getting sufficient protein. Many veterinarians (and even pet parents themselves) report good results from hydrolyzed proteins - but that’s not always the case.

In many of the studies cited that link a reduction in food allergies or IBS to a hydrolyzed diet, they often had ties to the pet food manufacturers in the first place. Independent research, on the other hand, could not find such definitive results. In fact, a 2016 study completed by Masuda,  Kenichi et al. found that anywhere from 20 to 50 percent of dogs fed hydrolyzed protein will still experience symptoms due to food hypersensitivity. The reality is, elimination of a food allergen is the most effective way to prevent a reaction. The best option for your dog or cat is to try different, single meat recipes. Feeding them a novel protein (a protein that your pet has never eaten before), is a great place to start.

Attempting to feed your pet the same protein they’re allergic to, just in a different format, is ineffective at best, and can be detrimental to your pet in the long term. Instead feed your dog or cat a new protein, such as rabbit cat food or limited ingredient dog food, to see if that eliminates their stomach upset. 


5. Artificial preservatives

Preservatives are formulated into nearly all pet food recipes, to ensure they have a long shelf life. Preservatives aren’t inherently bad, it’s just a matter of which preservatives are being used. Natural preservatives, such as Vitamin C, Vitamin D, Mixed Tocopherols (Vitamin E family), and Rosemary Oil are perfectly safe antioxidants that naturally slow the rate of oxidation down to preserve a product. Though these are safe options, many pet food companies instead choose to use artificial preservatives because they are much cheaper to manufacture. 

Not all artificial preservatives are bad, but there are some to be wary of. Two infamous additives are butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) which have both been identified as possible carcinogens for pets. They’re cheap ways to guarantee the shelf life of a product, and are used as a synthetic alternative to Vitamin C. Many manufacturers will claim that they are harmless, but studies have shown otherwise.

Ethoxyquin is another controversial additive used in pet foods. It has been banned in the European Union and Australia, but is still permitted by the FDA to be used in pet foods in the U.S. in small quantities. Ethoxyquin is commonly used in pesticides, and studies have linked it to certain forms of cancer. Fortunately, most pet food brands have removed it from their recipes due to the backlash from consumers. Still, it serves as an important reminder to be conscious of what preservatives are used in our pet foods, and to do our research before feeding our pets.


My Pet Eats One or More of these Ingredients… Now What?

If your pet has any of the above ingredients in their food - don’t panic! There’s still time to get them adjusted to a new diet. 

If you’re concerned about the quality of your dog or cat’s diet, check out KOHA Pet Minimal Ingredient Pet Food. All of our recipes are high quality, filler-free, and high in meat protein. For especially sensitive stomachs, we recommend our Limited Ingredient Diet entrées, for dogs and cats.

Before you switch your pet to a new food, make sure to transition, over the course of 5 or more days to avoid additional stomach upset. You’ll soon see the difference that a healthy diet can make!




Grognet, D. J. (2022, March 14). Bloat (or GDV) in dogs - what it is and how it's treated. American Kennel Club. Retrieved August 24, 2022, from

Masuda, K., Sato, A., Tanaka, A., & Kumagai, A. (2020, February 18). Hydrolyzed diets may stimulate food-reactive lymphocytes in dogs. The Journal of veterinary medical science. Retrieved August 24, 2022, from

Juncker, J.-C. (2017, June 7). COMMISSION IMPLEMENTING REGULATION (EU) 2017/962 of 7 June 2017 suspending the authorisation of ethoxyquin as a feed additive for all animal species and categories. Europa. Retrieved August 24, 2022, from

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