Limited Ingredient Diets: Itchy? Be Picky.

LID Food

Photo courtesy of Jackie Sheppard

If your French Bulldog suffers from a rash that just won’t clear up; if your Spaniel is nagged by a recurring ear infection; or if your playful Pit Bull stops in its tracks to chew its own feet — there’s a good chance your pet is suffering from an allergy.

CNN estimates that at least 10% of pets suffer from allergies, with food allergies accounting for 10% to 20% of those affected. Food allergies are the result of the body’s immune system mistakenly reacting to ingredients in a food as if it were a foreign substance. The most common food-based allergens include chicken, beef, pork, corn, wheat, and soy — all of which are widely used in commercially-available pet foods.
The signs of a food allergy can be similar to other allergies, ranging from mild skin irritation to chronic ear infection, and everything in between. Because of these unspecific signs, diagnosing a food allergy used to be costly, time-consuming, and frustrating.  But, with the advent of limited ingredient diets and the help of your veterinarian, pets — and pet owners — can find relief.

How limited ingredient diets work

Limited ingredient diets attempt to limit the amount of possible allergens to which your pet is exposed in order for your veterinarian to isolate the ingredient that causes the allergy.

There is no standard definition for what a “Limited ingredient diet” must be; however, most veterinarians (and by extension, manufacturers) agree that limited ingredient diets must have very few sources of both animal proteins and carbohydrates. Also, while many pet food companies advertise their foods as “limited ingredient diets,” only a select few sell diets that are rigorously manufactured and controlled in order to be sold as veterinary prescription diets.

Blum Animal Hospital offers diets from two companies whose products meet the requirements necessary to be prescription grade, and both of whom approach the limited ingredient concept with their own unique philosophy: Hill’s Pet Nutrition and Royal Canin.

Hill’s keeps it simple. Their Prescription Dietd/d line is formulated with only one complete animal protein (either venison, duck, or salmon), is free from soy protein, grain-free, and made with gluten-free ingredients.

Royal Canin takes a slightly different approach. Their “Selected Protein” diets opt for a few carefully selected sources proteins, often using a novel source (Whitefish, Duck, Venison, or Rabbit), but also using protein from their carbohydrate source (potatoes in the case of dogs; pea protein for cats), and hydrolyzed soy protein — a complete protein broken down into components that are unrecognizable to the immune system (i.e. hypoallergenic).

We Can Help!

Of course, there are many reasons for itching, rashes, and chronic ear infections, so it’s important to consult your veterinarian before making any changes to your dog’s diet. Visit us at or call us at (773) 327-4446 to make an appointment!

Written for Blum Animal Hospital by Jon Covert.