February 9, 2013
this article about food allergies in dogs is from my book “Healing Your Dog With Food” that is one of the bonuses in my Bulldog Health System:
Food allergies are often an area of blame in many dogs showing allergic reactions, but in actuality, only a small percentage of dogs suffering from allergies are actually food reactions. That said, I know about food allergies first hand because my Bulldog Archie is allergic to chicken which is the primary meat protein in most commercial dog food.
After several visits to my vet dermatologist who put Archie on an expensive “hypoallergenic” soy based diet for food allergies. Unfortunately the soy diet made his skin really ratty looking and didn’t solve the diarrhea problem.
So I decided to stop the soy experiment and try my own food trials. I noticed that every time I fed Archie a commercial diet with chicken he got diarrhea and itchy ratty looking skin. I no longer feed him chicken and he’s doing great.
If your vet has performed skin scrapings and ruled out parasites and fungus infections, you can perform simple dietary changes and see if your dog gets better.
Food allergies are difficult to diagnose because the symptoms can vary, including:
- Diarrhea or soft stools
- Severe itching
- Small sores with hair loss (not to be confused with mites)
- Secondary lesions from the itching
- Seizures, in severe cases
Hypersensitivity reactions tend to occur because the dog is reacting to one or two ingredients in the diet. These reactions tend to slowly occur over time because the dog is eating the same diet for several months, or even years, at a time. As the dog eats more of these allergens, they build up in the body until outward reactions begin to occur. Additionally, those dogs that experience seizures often do so because they are reacting to an allergen in their diet. Because of this, dogs that eat raw or minimally processed foods tend to not have food allergies and symptoms such as severe itching, skin lesions and seizures.
Although most skin allergies do not appear until the dog is one year old or older, food allergies tend to become apparent much earlier than this. Many dogs that are 6 months old or younger will begin to shows signs, but the majority of the cases diagnosed are in dogs over two years of age.
One reason that food allergies become apparent in young dogs is because their system is shocked by the dog food they are eating and they tend to have more intestinal parasites and viruses than older dogs. Parasites cause intestinal damage and this can cause a defective antibody response in the body. The antibody response allows for the body to allow food allergies to develop.
The only reason that dogs, and people for that matter, don’t develop a host of food allergies is due to something called “oral tolerance.” This is the body’s ability to ignore the foreign proteins that are found in the body. Otherwise, anything we ate we would become allergic to. This oral tolerance is believed to begin in dogs at about 6 weeks, which happens to correspond when most dogs are weaned. One way to assist puppies and prevent food allergies may be to wait until about 8 to 10 weeks to wean. This will also prevent other behavioral issues and the dog will be well prepared to begin a new diet at this time as well.
Unfortunately, the most common food items that dogs happen to be allergic to are the most common ingredients in all diets, whether commercially prepared or homemade. These foods include:
Many people believe that foods like lamb and venison are hypoallergenic proteins, but this is not the case. An animal can develop a food allergy to any type of food they are fed over an extended period of time.
Commercial prepared foods are often made with large amounts of grains because it is an inexpensive source of energy. However, these contain large amounts of carbs and gluten, which are two other ingredients that pets often develop an allergy to. For young dogs, you can actually improve their oral tolerance by limiting the amount of gluten and carbohydrates they ingest.
In diagnosing food allergies, you will need to feed your dog a Hypoallergenic Diet. This is the only way that you will be able to tell for sure that the dog has a food allergy. This diet takes about 3 to 12 weeks to complete. The purpose of this diet is to isolate the allergen in the food by banning all protein that the dog has eaten in the past.
The Hypoallergenic Diet
The use of this diet is designed to ban all protein that the dog has eaten in the past in an effort to determine which protein or other ingredient may be causing the allergic reaction. The diet will last about 8 to 12 weeks depending on the ingredients that need to be tested. Dogs that have food allergies will show a decrease in itching, and in some cases, the itching will stop all together.
There are two types of diets you can feed: homemade or commercial brands.
The homemade hypoallergenic diet uses 1 part protein and 4 to 5 parts cooked white rice. For those dogs that have never had protein such as turkey or lamb before, these are both good options. If you are not sure which types of protein the dog has had, it is advisable to try rabbit or venison, as very few dogs have eaten these in a normal diet.
Many commercial dog foods are now considered hypoallergenic because they have limited ingredients and few additives. Go to a specialty dog food store for the best diets made by small manufacturers. Every dog is an individual and there is no one-size-fits-all diet. That said, my current preference is for Nature’s Variety diets Prairie or Instinct (avoid chicken).
During the diet, you will feed your dog only the prescribed diet. This means no treats and no heartworm prevention medication. While on this diet, you should also avoid any supplements, as these often have agents used in binding the vitamins and minerals together, which the dog may be allergic to. You do not have to worry about any deficiencies developing in the short amount of time the dog will be on the diet.
You should see results in as little as a few weeks. Stools become normal, itching and scratching stop, small sores go away. However, if the severe scratching returns when the dog goes back on his regular diet, then you most likely have a food allergy occurring.
As the itching decreases over the 8 to 12 weeks, you can slowly begin adding back ingredients into the diet and watch to see if the itchiness associated with the food allergy reoccurs. You will add each ingredient until you have developed a well-balanced diet plan and the dog does not have an itching reaction. This diet can be fed long-term, as long as it is balanced.
Once on a homemade diet, many dogs may develop problems after being switched back to a commercial diet. These may include symptoms such as vomiting, diarrhea, and itchiness. In some cases this is due to the same carbohydrate or protein being used in the homemade diet is the same in the commercial diet. However, artificial flavorings, chemicals and preservatives are usually to blame in this situation.
Tips to Remember Regarding Food Allergies
- Occur non-seasonally
- Each dog is different
- Occur at any age, but most common in dogs 2 years or older
- Often allergic to beef, chicken, soy, wheat, fish, eggs, corn, and milk.
- Neither skin testing nor will blood testing accurately diagnose the allergen.
- Food allergies are less common than dermatitis