Most of us are already familiar with hypoallergenic products for humans – cosmetics, shampoos and the like, but what how much do you know about hypoallergenic dog foods? What exactly is a hypoallergenic diet, when is it needed, how can it help dogs with certain health conditions, and finally, how do you pick the right type of hypoallergenic dog food?
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In my practice I often encounter owners who look to switch their dogs to a hypoallergenic diet due to a variety of issues. I have previously wrote about the science on hypoallergenic dog foods and their effectiveness in this article, which I recommend to read to better understand how these diets work.
The below article will explain what you need to know about real hypoallergenic dog foods, what makes them hypoallergenic, what's hydrolyzed protein dog food diets, whether it's something you need, and how to shop for the best brand and avoid any “fake” hypoallergenic dog foods (of which there are several).
Hypoallergenic Dog Foods 101
The main reasons dogs may be put on a hypoallergenic dog food diet can be lumped into something called an “adverse food reaction.” This can either mean an allergy that causes the dog to erupt in skin lesions, ear infections or have gastrointestinal issues like diarrhea or vomiting.
Dogs with primary gastrointestinal disease such as inflammatory bowel disorder (IBD) can often suffer from some amount of adverse food reaction as well.
What are allergies in dogs?
The immune system is programmed to recognize and eliminate threats to the body, such as bacteria, fungi and viruses. When allergies occur, the dog's body is essentially tricked into thinking that a harmless substance is a threat. The fallout causes uncomfortable inflammation and subsequent disease.
Pollen, mold spores, even dust mite dander are common allergens (called antigens) that are otherwise harmless, but some pets' immune systems don’t see it that way.
Food allergies in dogs occur most commonly due to an overreaction to specific animal source proteins or carbohydrates in the diet.1
However, food intolerance in dogs that leads to an adverse food reaction is more common than a true food allergy.
Only about 10-15% of dogs develop a true food allergy. The most common antigens in dog food include proteins from chicken, beef, soy, dairy and egg.1 If a dog develops an allergy to a carbohydrate source, such as wheat, that means they are allergic to the protein component of the wheat.
Why certain bodies develop allergies and others don’t remains a medical mystery. We do, however, know that we can reduce the likelihood that pets will have these uncomfortable and dangerous reactions by feeding specific hypoallergenic dog food diets.
Dog food allergies or adverse food reactions are often diagnosed by what is called an elimination diet. In these “diet trials”, the dog is fed either a hypoallergenic dog food brand, or a single-source protein/carbohydrate diet, for 6-8 weeks. If the dog develops symptoms after returning to their normal diet, then an adverse food reaction can be diagnosed.
Many times, dogs diagnosed with adverse food reactions need to eat a hypoallergenic diet for the rest of their lives. This isn't a big deal, but it may be more costly to a pet owner since some hypoallergenic dog food brands are more expensive.
How can hypoallergenic dog foods help my dog?
Switching to an appropriate hypoallergenic diet will eliminate most or all allergy symptoms in your dog. This may take a little bit of trial and error.
Over time, hypoallergenic dog foods can help manage your dog’s chronic itchy skin or ears, making them overall more comfortable. It can also reduce their dependence on antihistamines, steroids and antibiotics. Dogs with chronic gastrointestinal problems can experience more firm stools and better weight maintenance.
Even though I will explain now how to shop for the best hypoallergenic dog food brand for your individual dog, if you are concerned about your pet or are interested in this diet, please make sure to consult with your veterinarian for details beforehand.
When is dog food considered “hypoallergenic?”
Hypoallergenic means below allergenic. When it comes to hypoallergenic dog foods, this term basically means that the structure of the potential allergen in that specific dog food recipe is so small that your dog's immune system can’t detect it.
There are several diets on the market that fall into the “hypoallergenic” category. They are all hydrolyzed protein diets, which makes the potential offending protein structure very small and much less likely to evoke a reaction from the dog.
This is what hydrolyzed protein looks like:
Even though it's marketed differently, veterinary experts prefer to call these hydrolyzed diets instead of referring to them as hypoallergenic dog foods.
According to Dr. Joe Bartges2, a board-certified veterinary internist and nutritionist, the reason proteins are hydrolyzed for hypoallergenic dog foods is because that disrupts protein structure in the food formula that removes any existing allergenic epitopes and allergens. This way it prevents the dog's body from recognizing that protein.
Proteins with molecular weights over 18,000 daltons are well-known to be the most antigenic, thus modification of proteins to compounds having lower molecular weight may be of benefit. When the average weight of the protein molecule is reduced to less than 18,000 daltons, this makes that protein source hypoallergenic.2
Even with the adjustments, all hypoallergenic dog foods are well-balanced and nutritionally complete for dogs to consume. Furthermore, consuming protein hydrolysates results in a quicker absorption of amino acids when comparing the absorption rate from whole proteins.
Hypoallergenic – A Catch-All Buzzword
As a pet owner, you must be careful when shopping for hypoallergenic dog foods, as this term is often misused. Limited ingredient diets are not necessarily hypoallergenic.
Sometimes, it may be necessary to consider a prescription hydrolyzed hypoallergenic dog food instead of an over-the-counter limited ingredient diet – it's less likely to be contaminated with allergens. Unfortunately, those are likely to be more expensive.
In a recent study, 12 commercial dog food products were tested for DNA of animal origin using PCR testing.4 The DNA included chicken, turkey, beef, mutton and pork. In 9 of 10 over-the-counter (non-prescription) limited ingredient dog food diets, DNA of one or more animal species other than what was declared on the label was found. The most common “contaminants” were beef and pork. Two prescription hydrolyzed diets tested in the study only contained DNA of the animal declared on the label.
Hydrolyzed diets provide short and long-term complete, balanced nutrition for adult and senior dogs. Most commonly vet recommended hypoallergenic dog foods are available from the three largest prescription diet companies that spend the most on research and science-based recipe formulations – Royal Canin, Hill’s Science Diet and Purina.
All these diets are very similar to each other, so you may often benefit more by simply choosing the cheap hypoallergenic dog food brand from either of these manufacturers. However, discussing with a vet is essential and if your veterinarian recommends one over the other, it is most likely due to geographical availability and their personal clinical experience using the diet with other dogs.
Here are some examples of vet recommended hypoallergenic dog foods:
Royal Canin HP Adult Veterinary Diet Hydrolyzed Protein
Main Ingredients: Hydrolyzed Soy Protein, Potato, Coconut Oil, Potato Protein.
Royal Canin Veterinary Diet Hydrolyzed Protein HS
Main Ingredients: Hydrolyzed Soy Protein, Brewer’s Rice, Chicken Fat, Beet Pulp.
Hill’s Science Prescription Diet z/d
Main Ingredients: Hydrolyzed Chicken Liver, Corn Starch, Soybean Oil.
Purina HA Hydrolyzed Dry Formula
Main Ingredients: Hydrolyzed Soy Protein, Canola Oil, Vegetable starch.
If your dog has multiple health issues, such as food intolerance and urinary tract problems such as struvite bladder stones, it is possible to feed a diet that supports both food sensitivities and urinary health. There are several recipes available, but here's one vet recommended:
Royal Canin Veterinary Diet Multicare – Urinary and Hydrolyzed Protein
Ingredients include brewer’s yeast and hydrolyzed soy protein. This diet also includes Royal Canin’s Urinary SO Index, which promotes a urinary environment unfavorable to the development of struvite and calcium oxalate crystals.
If your pooch is not a big fan of dry kibble, don’t despair. Both Royal Canin and Hill’s Science Diet provide canned versions of their hydrolyzed diets, particularly those mentioned above.
What About Hypoallergenic Dog Treats?
If your dog has now switched to hypoallergenic dog foods, complimentary hydrolyzed protein treats are available and recommended as well. If you feed one particular brand of hydrolyzed diet, be sure to stick with one from the same company.
For example, if you feed Royal Canin Hydrolyzed Protein PS food, select Royal Canin’s hydrolyzed protein hypoallergenic dog treats. Remember to stick with a hydrolyzed protein – don’t be tempted to switch to something else like venison or salmon, even if the label says its “hypoallergenic”.
Hypoallergenic dog teats that are commonly available:
Royal Canin Hydrolyzed Protein Canine Treats
Main Ingredients: Hydrolyzed Soy Protein, Brewer’s Yeast, Chicken Fat, Fish Oil.
Hill’s Science Diet Hypo Dog Treats
Main Ingredients: Hydrolyzed Chicken Liver, Corn Starch, Soybean Oil.
Hill's Prescription Diet Hypoallergenic Treats
Main Ingredients: Hydrolyzed Chicken Liver, Starch, Soybean Oil.
Semi-Homemade Hypoallegenic Dog Treats
If hypoallergenic dog treats are not available or are too expensive, you can try making your own. Top Dog Tips has a large database of homemade dog treat recipes, but this can be easily done by purchasing a complimentary hydrolyzed protein hypoallergenic canned dog food diet.
For example, if you already switched your pooch to hypoallergenic dog foods, and now he eats Hill’s z/d dry, you can purchase a can of Hill’s z/d formula and make treats out of it.
The process is simple:
Using your hands, roll out the canned dog food into a thin layer. Cut out the canned food into shapes of your choice. Stars, small circles, or dog bones.
Using a food dehydrator or an oven on low temperature (200 F or 93 C), bake the treats on parchment paper for 1 to 2 hours. Cooking time depends on the size and thickness of the treat. Check on them every 30 minutes until they are dry and crunchy. Store in a zip-top bag in the refrigerator for up to 2 weeks.
RECIPE: Hypoallergenic Homemade Dog Food (Video Guide)
The Bottom Line
Real hypoallergenic dog foods made with hydrolyzed proteins can make a big difference for certain dogs. Keep in mind that these diets are very similar to one another across the board, and sometimes it's not worth paying extra for a more expensive brand. That said, remember that some hypoallergenic dog foods are also not what they seem to be. If your dog is very strongly allergic to chicken, it may be wisest to select a hydrolyzed soy protein diet instead of a chicken-based diet.
Some diets may be available in your area while others won't, and your veterinarian may let you know about this. The reason being is because it's more expensive for the company to stock hypoallergenic dog foods everywhere, since they're not very popular to buy.
Many veterinarians will recommend one brand over another brand based on their own personal, clinical experience. If your veterinarian has had good results using a particular brand, consider giving it a try, but don't hesitate to get a second or third opinion either.