Food Sensitivity in Dogs

Picture of a sporting dog in a field

We all seem to worry about dog food and what we should feed our dogs. Even if your dog is healthy and has never had any problems with what he eats, you have probably wondered from time to time if you are feeding him a good dog food or if you should change foods. For some dog lovers, this issue is even more critical. Some dogs have food allergies and food sensitivities that can make it very difficult for their owners to find dog foods that they can tolerate. Food allergies are frequently discussed but are you familiar with food sensitivity in dogs?

Food allergy or food sensitivity: What’s the difference?

Let’s start by saying that dogs, like humans, can have food intolerances. This is a general term for adverse reactions to foods or an ingredient in a food. Dog food allergies are usually a response to a protein in a food. The protein doesn’t have to be a meat protein. Other food items also contain protein. The most common allergy triggers for dogs are chicken, beef, and dairy. Less common triggers include wheat, eggs, lamb, soy, corn, pork, fish, rice. Despite what you might have been told, allergies to grains are much less common than allergies to certain meats. If a dog does have a food allergy he is often allergic to more than one thing, unfortunately, which can make it even more difficult to find a dog food that he can eat. And, dogs with food allergies often develop allergies to more things as they get older.

None of these foods are harmful and most dogs can eat them without a problem. If a food is commonly used in dog foods, such as chicken or beef, it’s not surprising that some dogs will develop an allergy to them, simply because so many dogs are exposed to these proteins. But, if your dog happens to have an allergy to one of these foods, it can present a big problem.

With a food allergy, an allergic reaction is an immune response to a food. Your dog’s body will release histamines that cause itching, which leads to scratching. In many cases of food allergies in dogs the symptoms include itching, scratching, and skin problems. Sometimes the skin problems can become very severe if sores develop and infection sets in.

A food sensitivity is not an allergic reaction to a food but that’s not always comforting. A food sensitivity is an intolerance. In the case of food sensitivity, your dog might be sensitive to a certain ingredient in a food. The ingredient might cause your dog to have gastrointestinal problems such as diarrhea and flatulence. Lactose intolerance in dogs is an example of a food sensitivity. If your dog gets diarrhea when he drinks milk or eats dairy products, it could be due to a food sensitivity. Some dog foods even contain dried skim milk, whey, and other dairy products which might disagree with your dog. Or, if your dog gets diarrhea and flatulence when he eats dog food that contains peas, it might be a food sensitivity.

Dogs can have both a food allergy and a food sensitivity at the same time (lucky you!). One way to distinguish between food allergies and food sensitivities is that food allergies often cause skin problems while food sensitivities often manifest as gastrointestinal problems – though this distinction isn’t ironclad. If your dog has a chronic food allergy, for example, his intestines could be inflamed and he could have problems with diarrhea.

Are food sensitivities in dogs common?

Fortunately, no. Neither food sensitivities nor true food allergies in dogs are all that common. A 2017 British veterinary study found that among all dogs seeing veterinarians for a diagnosis, only 1-2 percent had food allergies or intolerances. Among dogs with skin problems, only 6 percent were found to have food allergies or intolerances. Among dogs with itching and allergies, about 20 percent were due to a food problem. So, even among dogs that have allergies, only 1/5 of dogs appear to have allergies that are related to foods.

Which dogs have food sensitivities?

Evidence suggests that any dog can have a food sensitivity. Males, females, spayed, neutered, and dogs of any age. Food intolerances can occur in any breed. There is some belief that allergies and immune responses can be genetic but more research needs to be done.

A first allergic reaction can occur in a dog that’s less than a year old. Many dogs don’t have a reaction to a food until they are 2-3 years old, however. Some dogs can have a first allergic reaction when they are 10 years old or more, even to a food that they have been eating their entire lives. An allergic reaction can occur for the first time at any point in a dog’s life.

It is important to know that your dog has to be exposed to a food item more than once before he can have a reaction. He can eat something the first time without any problem. But when he eats the same item later (whether it’s the next time or 10 years later), his body, for whatever reason, reacts to it as a foreign substance and produces histamines for the allergic reaction.

A food sensitivity may show up sooner in a dog’s life. For example, with lactose-intolerance, puppies are able to nurse from their mothers but after a few months some dogs lose the enzyme to digest lactose. After this point they might have diarrhea if you try to give them milk in a bowl. With a food sensitivity your dog can apparently react the first time he eats something that disagrees with him.

Symptoms of food sensitivity in dogs

If your dog has a food sensitivity you will probably see the following symptoms:

The good thing about a food sensitivity for your dog is that it’s not as bad as a dog food allergy. It’s usually easier to avoid the kind of ingredients that your dog might be sensitive to as opposed to some of the ingredients that tend to cause allergic reactions. If your dog is sensitive to potatoes, for example, you can find a lot of foods that don’t contain them. On the other hand, if your dog is allergic to one of the common meat proteins such as chicken, beef, lamb, it makes it a lot harder to find a good dog food for your dog.

The other good thing about a food sensitivity is that it usually appears as soon as your dog eats something he can’t tolerate so you have a better chance of identifying the food/ingredient that causes the problem. The problem is also over as soon as your dog has eliminated the ingredient from his body, from one end or the other.

Granted, it’s not exactly fun to deal with any dog health issue that involves gastrointestinal problems for your dog but food sensitivity is something that can be managed and avoided in most cases.

Identifying your dog’s food sensitivity

As mentioned, many owners can identify a problem ingredient right away because their dog will have a reaction to a food/ingredient within just a couple of hours of eating something that disagrees with him. If you have any doubts about what is causing your dog’s problem, talk to your veterinarian. S/he may recommend the same kind of elimination diet that is used to identify an allergen in dogs with food allergies.

One word of caution – don’t assume that your dog has a food sensitivity every time that he has a case of diarrhea or vomits something up. It’s always possible that your dog might have a little stomach virus, or he ate some trash , etc. Dogs have all kinds of adventures with their G.I. system that are not normally anything to worry about. If you see blood in his stool or vomit, take him to the vet. That’s important.


Food intolerances, including food sensitivity, are not as common in dogs as many people assume. However, they do occur. If you think that your dog has a food sensitivity, try to identify the food or ingredient that might be causing the problem. If you have changed to a new food, there could be something in the food that disagrees with your dog so discard the food. Food sensitivities are usually identified by gastrointestinal problems. If your dog continues to have symptoms, see a veterinarian.



Leave a Reply

Your email address will not be published. Required fields are marked *

Table of Contents