If you go into any pet store you will likely find that many of the foods on the shelves are marketed as ‘Hypoallergenic’, there are also an increasing number of dog owners mentioning that their dog has allergies, often ones that are food based.
While there is no doubting that food allergies do exist, they are actually not as common as you may think. Sometimes there can be other environmental or medical triggers, and sometimes it may not actually be an allergy, but something else entirely.
Of course, if your dog does have a food allergy then it is important to make sure that you pick a food that is going to work for them. There is no one size fits all ‘best’ dog food for allergies. It will depend on what your dog is allergic to and in what quantity, sometimes if they only have a small amount of something, it is not enough to trigger a reaction. The trick is working out exactly what is causing the reaction and then finding something that does not contain this.
If your dog is scratching and has inflamed skin or ears, it could be a sign they have an allergy and sometimes this can be as a result of the food they are eating
- Rule Out Other Conditions First
- What is the Difference Between an Intolerance and An Allergy?
- Do Allergy Tests Really Work?
- The Importance of an Exclusion Diet
- What Are ‘Hypoallergenic’ Dog Foods
- Prescription Diets For Food Allergies
- Home Cooked or Raw Diets
- Novel Single Protein Source Diets
- Low Grain or Grain Free Diets
- Vegetarian/Vegan Diets
- Be Aware That Labelling is Not Always Transparent
- Recommended Further Reading
Rule Out Other Conditions First
If your dog is suffering from symptoms that suggest they may have an allergy of some sort, we would always recommend consulting with your vet. If they are severe there may need to be some pain management until you can work out what the cause is and it is also important to make sure that it is not some other underlying condition that is causing similar symptoms to those you see in an allergic reaction. Things like pancreatitis or infections or viruses can all create symptoms that may lead you to believe that your dog is suffering from allergies.
What is the Difference Between an Intolerance and An Allergy?
Sometimes people will say that their dog is allergic to a specific food but actually, they may only be intolerant to it. While an intolerance is still something that needs to be managed, it is not the same and it is important to be able to make this distinction.
An allergic reaction occurs when your dog’s body interprets the protein within a food item as being something it should not accept. This triggers an immune response and this can manifest itself as inflamed or itchy skin, sore ears and sometimes a response within the gastrointestinal tract which can cause vomiting and diarrhoea.
It is actually more common for allergies to be triggered by environmental factors rather than food, things like grass, spring flowers and parasites like fleas can also cause allergic reactions. Sometimes it can even be a combination of things. We would always recommend making sure that your dog is regularly treated against parasites like fleas to prevent a problem developing with this as it is an even more common problem than a true food allergy.
Gastrointestinal reactions are also common if your dog has an intolerance to something, rather than an allergic reaction. The two are commonly confused. An intolerance is when something doesn’t agree with your dog but it is not causing an allergic reaction. Sometimes intolerances only occur if your dog has too much of something for their stomach to handle but it can also be that they are very sensitive to that particular ingredient and even a small amount can cause stomach issues.
Of course, for both, you ideally want to work out what food it is that is causing the problem so that this can be eliminated from the diet.
Do Allergy Tests Really Work?
Allergy testing is becoming an increasingly popular method of ‘diagnosing’ what allergies your dog may have. There are tests that can be run by your vet and they are even possible to get as an online kit.
To date, there are no conclusive scientific studies that validate that these types of tests are accurate. They are still widely used though, can cost the owner a lot of money, and are often not even providing them with inaccurate information.
This study published in the Veterinary Journal in 2019 illustrates that serum and saliva testing is not particularly valuable when it comes to allergy diagnosis and illustrates the validity and importance of conducting an elimination or exclusion diet.
The Importance of an Exclusion Diet
Most respected veterinarians with a background in nutrition suggest that the most foolproof method of establishing what your dog is allergic to is to perform an exclusion diet.
It is not always an easy process and it requires diligence, patience and being very strict. If you can stick with it though, in the long run, it will make things much easier for you and more comfortable for your dog.
A true exclusion diet should last for at least 10 to 12 weeks. Sometimes it can take a number of weeks for all the allergens to truly leave your dog’s body and for their immune system to fully settle, so only doing it for a short period of time will not give you accurate results.
During this time your dog cannot be allowed any other food sources. They cannot have the opportunity to scavenge any tidbits or table scraps. This is extremely important! Often people do not think about things like oral wormers, chews with a flavouring or picking things up they are not supposed to outside. If your dog has an extreme allergy, even the smallest amount of something that causes a reaction for them can be enough to mess up the results of the trial.
If there is an improvement in this time it is usually suggested that they then go back onto the old food for a short period and if the reaction happens again then it is likely that you know it contained an ingredient that did not work for your dog. The reason that it is important to retest is that sometimes your dog may have been having an environmental reaction rather than food reaction, and it may have just coincidentally settled down during the exclusion diet period. If this happens it may lead you to believe that the food has been the cure when actually it was nothing to do with the food. The retest will allow you to double check this, if they do not have any reaction to the old food the second time around then perhaps you need to consider if it could have been other treats you were feeding or an environmental allergy instead.
An exclusion diet will normally be one that is incredibly simple and usually contains a novel single source protein and carbohydrate source, that they have never tried before.
Sometimes this can be home cooked, sometimes it is a commercially available one and sometimes it can be a prescription diet.
While your dog is on an elimination diet, it is very important that they are not given other chews or treats that could impact on the accuracy of the results
What Are ‘Hypoallergenic’ Dog Foods
Sometimes, if someone wants to put their dog on an exclusion diet or one that is suitable if their dog has a food allergy, they may see a dog food labelled as being ‘hypoallergenic’ and assume that this will enough and put their dog on this. This term has become too commonplace and it can be very misleading.
While hypoallergenic foods often contain fewer protein and carbohydrate sources, because every dog is different with what ingredients they may be allergic too, they are not what would normally be recommended for dealing with an allergy. Instead, as explained, it is better to pick a simple food with one novel protein and carbohydrate source for the main ingredients.
Sometimes a food may be labelled as ‘Hypoallergenic’ but that does not mean it will stop all food allergies for all dogs
Prescription Diets For Food Allergies
There are a number of prescription diets that have been specifically developed for use for an exclusion diet and sometimes even for long term use. These diets are ones that contain hydrolyzed proteins. Hydrolyzation is a process that involves breaking down the protein in the food so that the dog’s immune system does not have the same response it would when the protein source is whole.
They are also foods that, because they have been developed for dealing with allergies, have often been produced in very careful factory conditions. This means there is a lesser risk that the food could have been cross-contaminated, which can mess up the results of a trial.
It will not work for every allergy but it can be successful in many food allergy trials.
It is not a cheap option, although some pet insurance policies will cover the cost, and it is a diet that should be introduced in discussion with your vet.
Some people choose to start with a prescription diet for the purposes of the elimination trial and once they have established what seems to be working for their dog, they will then introduce an over the counter, more widely commercially available dog food at this point (one again with limited ingredients).
Below are a couple of hydrolyzed protein diet options for your dog.
Royal Canin Dry and Wet Hydrolyzed Protein Dog Food
Royal Canin produces both a wet and a dry variety of dog food with a hydrolyzed soy protein source. It can be useful for the purposes of doing an elimination diet and some people leave their dogs with particular allergies on it as a long term diet choice.
Both are considerably more expensive than most non-prescription diets so it can be an expensive option, especially if it is one that you plan to continue for your dog long term.
The dry food is not as palatable as some higher meat content foods and this is when the wet food variety can be useful. It is even more expensive than the dry version though and more attention may be needed to be given to your dog’s teeth cleaning regime on an exclusively wet diet too.
Purina HA Hydrolyzed Protein Dry Dog Food
Purina also produces a hydrolyzed protein prescription diet. Again, like Royal Canin, it is available in a dry and canned formula. It is also on the pricey side, although it usually works out at slightly less than the Royal Canin option. If it allows your dog to be comfortable and free from inflammation and itchiness then, it could be worth it. It is also worth checking out whether your insurance policy may cover the cost of the food. It doesn’t happen often but, if it does, it could save you a lot of money.
Home Cooked or Raw Diets
A home cooked diet can also be a good way of ensuring that there is no cross contamination and that the ingredients that you are using are simple and novel.
It is generally recommended that this diet is developed with the advice of a veterinary board-certified nutritionist though to ensure that your dog will get the right balance of nutrients that they would need, especially if you plan to feed like this long term.
With raw diets, care should also be taken to ensure that it is appropriately balanced and you should be aware that there could be a greater risk of germs and bacteria causing stomach upsets.
Novel Single Protein Source Diets
If you are opting to do an elimination diet using a store bought food, then it is best to select one that has only got one single source protein and carbohydrate source, and both of these should be novel, something that your dog has not tried before.
Ideally, it should not have a long list of additional ingredients as this makes working out what is causing the problem potentially more challenging.
Don’t forget to check the full ingredient list as sometimes, even when a food is labelled as being a particular protein type on the front, it may have other protein sources included within the ingredient list (fish oils are a common example of this).
Some options for single source protein dog foods are detailed below.
Merrick Limited Ingredient Dry Dog Food
This single source protein diet does not contain as many ingredients as many other commercial dog foods. It is also a well-reviewed and respected brand. The Limited Ingredient range is available in 5 protein varieties, although none of them are exceedingly novel, so if you have exposed your dog to all the meat types they contain, you may need to try a different diet for doing your elimination diet.
They also do a wet food variety of this range, this can be useful if you have a particularly fussy dog.
Zignature Kangaroo Formula Dog Food
If you are looking for a very novel protein source, one that your dog is not as likely to have tried before, and in a food that does not have other protein sources added to its ingredient list, then the Zignature Limited Ingredient range might be a good option to try. As well as the unusual kangaroo meat formula, they also do a venison variety. If your dog is a bit of a fusspot you could mix in or feed wholly their wet food option.
Cheaper than the prescription diets, this is still a food that is on the pricey side but it is well-reviewed.
Earthborn Holistic Venture Rabbit Grain Free Dog Food
This is another brand that has a range of limited ingredient formulas and the rabbit variety provides another novel protein source option. Their carbohydrate source is also novel, being pumpkin instead of the more common rice or potato. The brand is known for being high quality and the meat is sourced from ethical producers.
Low Grain or Grain Free Diets
Grain Free Diets have become increasingly popular over the last decade. They are often suggested as being a ‘cure all’ for dietary intolerances and allergies. While it is true that some dogs can be allergic to grains, usually it will only be a particular type of grain and they may be fine with another kind. Grains are not necessarily as bad as the marketing of the grain free foods often suggest, and sometimes your dog could actually be allergic to the grain free carbohydrate source.
If your dog has been using a grain-based food, you may wish to try a grain free option so that you can pick a novel carbohydrate source, but it should not necessarily be because it is perceived as an overall better diet option.
A lot of the single source protein options are more readily available in grain free options than those with grains, some of those are already detailed above.
If you want to try a vegetarian or vegan food for your dog for ethical, medical or allergy reasons, then we would always recommend taking advice to ensure that the food that your dog will be getting has an appropriate balance of nutrients, vitamins and minerals. The food should also be formulated to meet the Association of American Feed Control Officials (AAFCO) guidelines.
Some vegan diets are not formulated to provide enough of the essential amino acids that your dog needs to stay healthy. They can be low in things like taurine or l-carnitine and this deficit can increase the chances of developing certain health conditions.
Plant proteins are often not as easy to digest as a meat-based protein and this can lead to gastric upsets and problems for growing puppies. They also need to be getting the right amounts of fatty acids, something that can be difficult to achieve with a vegan diet and this is why you often see a deterioration in coat condition with dogs being fed this type of food.
There are some dogs that do really well on one of the more balanced vegan diets though and if this is a route you would like to investigate for a dog with allergies then take advice from your vet and/or a qualified canine nutritionist and select an AAFCO labelled food.
It is important to also be aware that a vegan diet for a cat is not appropriate as they have different nutritional requirements from a dog and the levels of taurine they require is much more significant.
V-Dog Vegan Dry Dog Food
The V-Dog range is one of the more highly regarded vegan dog food options. They follow the AAFCO guidelines and it is well reviewed by its customers.
Natural Balance Vegetarian Dog Food
This food is another one that conforms to the AAFCO guidelines and it is one that offers better value for money than some brands too. They also produce a wet food variety too which can be useful as a topper for fussy dogs, great for stuffing interactive toys like a Kong, or for using as a complete diet.
Be Aware That Labelling is Not Always Transparent
It is important to always read the label. Sometimes a food may be marketed as ‘chicken and rice’ for example. When you actually check the packaging though it may have lots of other protein or carbohydrate ingredients in it too. These types of food would not be a good choice for using during an elimination diet as it will then make it too challenging to narrow down what ingredients could be causing the problem, and it also means that there is more chance of your dog having a reaction in the first place, given the greater number of ingredients.
Some foods may be open to cross contamination too. Doing your research and finding out how products are manufactured and packaged can also be useful.
Recommended Further Reading
If you want to understand more about your dog’s diet in general, then you can’t go wrong with Dr Linda Case’s book Dog Food Logic. It focuses on the science and facts rather than the marketing and hype.