VETERINARIAN JULIJA ABRAM: HELP, MY DOG HAS A FOOD ALLERGY! OR DOES IT?
29.03.2022
Food allergies have been discussed quite a lot in recent years. Many owners suspect reactions to chicken or all kinds of grains in their pet’s food, while in reality, the confirmation of food allergy through an elimination diet is usually not done. Therefore, all that remains is the owner’s assumption and belief that the animal is allergic to that same chicken, beef, or grain. It should be noted that food allergy as such is one of the rarest forms of allergy – much more common are environmental allergies, which may be related to dust mites, pollen, grass, or even fleas.
What is a food allergy?
A food allergy occurs when the animal’s immune system reacts to a protein component of food as an enemy and involves the immune system in the reaction. The result of such a reaction can be itchy skin or ears, some animals may develop skin inflammation, while others may experience vomiting and diarrhea. Some unlucky individuals may suffer from both skin and gastrointestinal issues simultaneously.
Food allergies are often confused with food intolerances. In the case of food intolerance, the immune system is not involved – the body simply lacks the ability to properly digest a particular food. Food intolerance typically manifests as digestive disorders – vomiting, bloating, gas, diarrhea – but can also include skin rashes, itching, poor skin and coat condition, chronic ear or paw inflammation.
Indeed, clinical symptoms are very similar to allergic reactions. Moreover, there are many other skin and gastrointestinal diseases that look exactly like food allergies. Therefore, close cooperation with a veterinarian and patience are very important in identifying the cause of the problem.
How to diagnose food allergies?
To understand whether a pet truly has a food allergy or not, a veterinarian puts the animal on a specific diet. This could be a hydrolyzed protein diet or a diet containing one specific protein source and one specific carbohydrate source (in addition to necessary fats, vitamins, and minerals). The selected protein and carbohydrate sources must be something the animal has not been exposed to before (has not consumed). The animal must be on the selected diet (either selected protein + selected carbohydrate or hydrolyzed diet) for one to two months. During this period, all treats, chews, and any other food items that the pet might consume must be excluded from the menu. If the pet’s clinical signs significantly improve during this period, a provocation test is performed – the old food is reintroduced. If the pet reacts to the old food with previous symptoms – skin itching, diarrhea, etc., then the pet is switched back to the special diet. If the symptoms are under control, new food items are gradually introduced to the pet to determine which food/protein exactly triggered the reaction. Unfortunately, not all owners are willing to do the provocation test, which means that it remains unclear whether the animal actually had a reaction to the food or if the reaction was due to seasonal factors, such as pollen. The whole process is, of course, long and tedious for the pet owner.
Blood tests are also popular, claiming to identify what the animal is allergic to. Unfortunately, it has not been proven that such blood tests are very effective – see, for example, this study. Moreover, these tests are very expensive.
Not all hypoallergenic diets are equal
Hypoallergenic clause diets are sold both in pet stores and veterinary clinics. Unfortunately, not all such diets are equally effective because the term “hypoallergenic” does not have a universally agreed meaning in the pet food world, which also allows manufacturers to use the term more broadly. In cases of allergies, each case is approached individually – a chicken-containing diet may be hypoallergenic for one animal, but not for another. The same goes for, for example, lamb, ostrich meat, kangaroo meat, or duck. If we regularly feed our pet food with some exotic meat, we simply increase the likelihood that the pet will develop an allergy to the offered exotic protein. This is not a rule. The situation should be viewed like this – allergy can only develop to the protein the animal has been exposed to.
When it comes to hypoallergenic diets sold in clinics, they are usually either hydrolyzed protein (and hydrolyzed carbohydrate) or single-protein diets. In hydrolyzed diets, the protein component of the food (sometimes also the carbohydrate component) is cut into such small pieces that the immune system does not recognize it as protein and therefore does not react with an allergic reaction. Single-protein diets use the principle of one protein-one carbohydrate source (sometimes also selected protein and carbohydrate sources) – in addition, the food contains necessary fats, vitamins, and minerals.
More attention is also paid to avoiding cross-contamination with clinically sold special diets. This means that during food production, every effort is made to ensure that no potential allergen gets into the food. However, in factories that produce several different foods and use the same production lines, the risk of cross-contamination can be very high. Due to the risk of cross-contamination, many human food manufacturers label their packages with “may contain nuts or seeds” even if the food does not seem to be related to nuts or seeds at all.
Which foods are associated with allergies in pets?
Although true food allergies in dogs and cats are quite rare, there are still some foods that are more commonly associated with allergic reactions – these include chicken, beef, dairy products, and eggs (fish in cats). This is primarily because these are the proteins most commonly used in pet food production – the more animals consume a certain protein, the greater the likelihood that individuals with allergies will emerge – the sample being studied is simply larger. Many may be surprised to learn that grains are actually a very unusual cause of food allergies – most pets that have any allergic reaction to food react to the protein component of the food. However, it may happen that a pet is allergic to, for example, potatoes or carrots.
Fear of allergies is exploited in the pet industry, and thus foods are produced with fancy labels like “grain-free,” “chicken-free,” “hypoallergenic,” “gluten-free,” etc. Speaking of gluten – gluten intolerance in dogs is extremely rare. So far, it has only been diagnosed in Irish Setters, and it is suspected to occur in Border Terriers, but it has never been diagnosed in cats.
Conclusion
True food allergies in pets are very rare, and when they do occur, they typically involve a protein, not a carbohydrate source. It’s important to be cautious about various products that capitalize on food allergy fears to boost their products. Not all hypoallergenic foods are equal, and despite the proud slogan, a product may still trigger a reaction in the animal, especially if there was cross-contamination during manufacturing. If a veterinarian has diagnosed a food allergy in a pet through an elimination diet, it’s important to adhere to the veterinarian’s recommendations for future food choices.
For such pets, finding treats can be quite challenging. However, if the pet has not previously consumed venison or lamb, FoodStudio’s venison- or lamb-flavored dog broths could be a great treat, appetite booster, or snack. For example, my dogs love to lick and chase frozen dog broth cubes on the floor. It provides them with activity, mental stimulation, and a taste experience. Additionally, FoodStudio dog broths help maintain the dogs’ body condition because the products are essentially fat-free. Seriously! They’re so high quality that I consume them in my own smoothies – after all, they’re a source of collagen – and I hope that the massive collagen content in the broth helps smooth out the life experience wrinkles around my eyes.