Sad pug stares at the floor.

The most common eating issues in dogs, and what causes them

What’s plaguing your pup’s gut? Learn about the most common s
tomach & allergy issues in dogs, and what causes them

We can all remember a time in our lives when a meal we had just didn’t sit right, or worse – it made you downright sick. Maybe it was the first time you tried shrimp in the fourth grade, and you left uncle Larry’s beach house with a rash so bad you’d rather be sunburned all summer long. Or maybe, it was way later in life, when you tried jumping on the quinoa bandwagon only to realize that those tiny seeds might as well be itty bitty bullets raining fire on your unexpecting gut.

Well, at least you know where the Pepto is.

Your dog, however, can’t exactly crawl to the medicine cabinet when nausea, heartburn, indigestion, upset stomach, and diarrhea strike. And what about allergic reactions? Without being doggy mind readers, it can be pretty difficult to diagnose issues. But what you can do is prepare yourself with enough of an understanding of what signs to look for when food-related eating issues arise – and even better, be proactive by feeding your pup complete and balanced, nutrient packed food (like our Happy Howl recipes!


Let’s take a look at how a dog’s digestive system works

A dog’s digestive system involves 4 main steps for processing food:

  • Chewing and eating (the mouth & esophagus)
  • Storing and breaking down food (the stomach)
  • Absorbing nutrients (the small intestines)
  • Turning used mush into poop (the large intestine and colon)

  • So when any food-related issue arises for your dog, the vet will typically try to pinpoint which step of the digestive journey the issue is happening during by asking you plenty of questions about your dog’s habits, age, appetite, diet, and so on (make sure you know all these answers!). 

    But most of all, you’ll need to know the signs or symptoms they’re displaying, which are crucial to determining which part of the digestive system their issue is affecting, and whether it’s an allergy, a stomach issue, or something else being caused by their food.


    Lookout for these common signs of food-related allergies 

    • Itchy skin
    • Trouble breathing or wheezing
    • Vomiting
    • Diarrhea
    • Weight loss/no appetite
    • Loss of energy/lethargy

    Just like in humans, food allergies can affect dogs externally and internally. Itchy skin, scratching, and a lack of energy can all be signs that your pup is reacting to one or more ingredients (usually proteins) in their food that don’t agree with them. 

    (Your dog might also be allergic to plants, insects, or animals, all of which are classified as different allergies based on the allergen causing it – such as flea bites, or other insect bites, which cause irritation and itching. But, coughing and wheezing can be telltale signs of an inhalant allergy, or “atopy,” typically caused by allergens like mold spores, dust, or tree pollen.)

    But food allergies or sensitivities can develop as a reaction to both proteins and carbs in food. This could include dairy, wheat, proteins like beef, chicken, lamb, or eggs, and even soy. Many of the symptoms and signs listed above can be signs of an allergy to these typical ingredients. 


    How to determine your dog’s allergy with an elimination diet

    The most practical way to find out if your dog is allergic to any ingredients in their food is by narrowing down what your dog might be allergic to, one ingredient at a time. This is known as an elimination diet. (It’s an alternative to having tons of extensive testing done – if you’ve even tried to determine your allergies at an allergist, you’ll know this is true, and can be a long, expensive process.)

    DID YOU KNOW: Our founder, Colin, used an elimination diet to see which ingredients, if any, were causing the reactions his pal Rocky was having to certain foods. (That’s how Happy Howl was born! After months of trying different foods and ingredients, Colin’s research and trials led him to the perfect recipe. You can read more about Colin and Rocky’s journey here! 

    According to an article by Catherine Barnette, DVM and Ernest Ward, DVM of VCA Hospital, “because it takes at least eight weeks for all other food products to be eliminated from the body, the dog must eat the special diet exclusively for eight to twelve weeks. If a positive response and improvement of your pet's clinical signs occurs, your veterinarian will advise you on how to proceed.”

    It’s typically best to try an elimination diet by making homemade meals for your pup, so you can control the exact ingredients and proportions, in order to make any determinations.

    It’s important to keep in mind that symptoms of food allergies can also overlap with symptoms of non-allergic digestive issues. Diarrhea and vomiting, for example, can be just as telling a sign of an underlying stomach or intestinal disease, such as gastroenteritis or malabsorption – which can be caused by infection with bacteria, viruses, parasites, medications – OR, new foods.


    Common signs of digestive issues, disorders, and diseases caused by food

    • Drooling
    • Diarrhea
    • Constipation
    • Vomiting
    • Regurgitation
    • No appetite
    • Bleeding
    • Abdominal pain
    • Bloating
    • Straining to go to the bathroom
    • Dehydration

    The signs above can be symptoms of many different issues (which we won’t get into this time), but they can also be clues to diet-related issues that your pup might be displaying – which you might not be aware of. From an unbalanced diet to toxic foods, let’s take a look at some of the possible causes of digestive and stomach disorders in doggos.


    An unbalanced diet – the opposite of a complete and balanced diet

    What does complete and balanced mean? You’ve probably seen this on several dog food labels. This means that, according to the FDA, the brand of dog food has:

    • Met one of the Dog Food Nutrient Profiles established by the Association of American Feed Control Officials (AAFCO) – for a product to meet one of the AAFCO nutrient profiles, it must contain every nutrient listed in the profile at the recommended level
    • Or, it has passed a feeding trial using AAFCO procedures – feeding trials are when AAFCO tests whether or not the food meets the complete and balanced standard within a specific stage of dog life, such as puppies (growth stages), or all stages of life.

    On the contrary, an unbalanced diet would consist of your dog being fed table scraps instead of meals, or just a daily pet food that doesn’t meet the complete and balanced standards, which in other words, is not deemed healthy for sustained feedings.

    Imagine, only eating McDonald’s Chicken Nuggets every day of your life. Or just eating milk and cheerios 24/7. As humans, we need to meet a minimum nutritional balance in our own lives, or else we start seeing the side effects of it too. And when little Fido is mostly surviving off scraps of byproduct “meat,” he or she is certainly not getting their much-needed nutrients. 

    So be sure to truly understand what’s in their meals (especially kibble – which we’ll get to in a bit), and look for any of the above side effects as signs that they might be experiencing from this type of malnutrition – they should be pretty obvious.


    Other key digestive offenders can be toxic foods

    If you’ve never googled searched this topic before as a doggo owner, then it’s important you remember this next list! All of the following foods, in some way or another, are toxic to your pup. But these are just a few! And if you’re ever going to feed your pal human food for any reason, always make sure it’s ok for them!):

    • Xylitol – found in candy, gum, and some baked goods, can cause vomiting and even liver failure
    • Avocado – you might love it, but for pups it can cause vomiting and diarrhea
    • Onions and garlic – can kill their red blood cells and cause anemia, vomiting, and so much worse
    • Grapes and raisins – seem harmless right? They are awful for dogs and can cause kidney failure and multiple episodes of vomiting a day
    • Caffeine and chocolate – tea, coffee, cocoa, soda – all of it is bad for the pups and can cause vomiting, diarrhea, tremors, and it can be fatal
    • Milk and dairy – sadly it’s not a good idea to give your pup ice cream, it can cause diarrhea, digestive issues, and even allergies 
    • Macadamia nuts – these make the no-no list because even a few can make your pup vomit and become very ill
    • Fat (from meats) – contrary to cartoon beliefs, dogs should not be eating fat, because it can cause pancreatitis 
    • Raw meat and fish – it’s worth it to avoid feeding these to your pups unless you’ve sought expert advice (or you’re a super scientist who is well versed in food-related bacteria)

    Again, the above are just a few of the big ticket items to avoid. There are also several seeds, fruits with pits, and other no-no’s like salty snacks (or high amounts of salt in general) that should be avoided for your poochy pup. So always do your research!

    Kibble, crash diets, and other dog-food offenders that can affect the digestive system

    Kibble is a highly controversial topic on its own. But there’s no doubt that vets are saying to sway from this traditional (archaic) form of feeding your dog. Over the years, many thought-to-be benefits of kibble have been debunked by food scientists and vets alike, and the outcomes of their research all point to: kibble is over processed “cereal” for dogs, and not a healthy way to feed your best friend. Especially if it’s the only thing they’re getting in their bowl.

    On top of that, many brands of kibble have been found to cause food sensitivities in dogs, and can also cause their digestive tracts to dry up from dehydration. All in all, it’s not the best choice for your best friend, especially since for the last 80-something years that kibble has been around, “chronic degenerative diseases, auto-immune diseases, allergies, kidney, pancreatic and liver disease are all rampant within our pet populations and cancer rates continue to rise,” as Roxanne Stone MSc explains in this anti-kibble article.

    Crash diets – or otherwise, a drastically-changed diet that shocks a dog’s body to trigger weight loss, can also be the cause for many digestive issues. Dogs do best on a complete and balanced diet, so if your pup is skewing to the overweight category, it might be worth looking into what’s in their food – whether it’s kibble, high carb content, over feeding, or even excessive treats. Following a feeding schedule that’s calculated per your dog’s weight and breed is a great way to stay on top of weight issues. After all, diets can be stressful enough, there’s no reason to make our beloved pups go through that kind of stress if we can avoid it!

    Instead of trying diets as a way for your pal to lose some pounds, simply calculating the proportions of wholesome, nutritional meals for your pup is a great way to go. (That’s actually how Happy Howl works – not only are our meals complete and balanced, but we also take your pup’s stats into account, like weight, age, and breed, and use those to calculate the perfect proportion for each of their meals.)

    Even switching to a new brand of food too fast can cause digestive issues. Think about times when you’ve jumped into a new meal plan, or even tried something entirely new cuisine-wise – like sushi for the first time. It can be a shock on your stomach, and cause anything from a light upset to major issues. That’s why it’s important to follow a transitional schedule when switching to any new brand of dog food. (At Happy Howl, we provide a specific transition schedule for your doggo to follow so they don’t experience any unwanted symptoms due to switching their diet.)

    Doggie digestion can be a tricky battle at times. But it all comes down to paying careful attention to your best pal and what signs their showing. After all, good food should have them acting and looking their very best – that means more tail wags, happier playtimes, and a shinier, healthier coat and skin. If they’re not showing the “good” signs, then maybe it’s time to pay closer attention. Just keep in mind, one bout of diarrhea isn’t cause to freak out. But if stomach issues and allergies are plaguing your pup’s gut – we’re here for you, and that’s exactly why we started our mission to help dogs in the first place.

    Always consult a vet if your pet is experiencing prolonged symptoms of allergies or stomach conditions. Because our dogs can’t tell us what’s wrong, it’s always best to be on the more cautious side. 

    Back to blog