Prescription pet food — Food as medicine or feed-grade scam?

Analysis by Dr. Karen Shaw Becker

prescription diet pet food

Story at-a-glance

  • There are more and more “prescription” processed dog diets entering the marketplace
  • These diets are being recommended to pet parents, often to deal with a dog’s health condition due in whole or in part to a lifetime of eating processed pet food
  • Processed prescription diets are no more species-appropriate or high-quality than regular processed pet food
  • Despite what you may have been led to believe, most conventional veterinarians aren’t good pet nutrition resources
  • Your best source for this information is a vet who has independently studied animal nutrition and can create customized, nutritionally balanced, species-appropriate diets

If you're a pet parent, you've probably noticed not only the mind-boggling array of dry and canned dog foods on the market, but also the trend toward "specialized" diets marketed for small dogs, large breed dogs, older dogs, dogs of certain breeds and so on.

We're also seeing more and more "prescription" diets advertised for dogs with a wide range of health conditions such as kidney or liver disease, joint disease, obesity, food intolerances, gastrointestinal (GI) disorders, cognitive dysfunction, urinary crystals and stones, diabetes, heart disease, cancer, dental disease and recovery from an accident, surgery or illness.

The mainstream pet food industry as well as many in the conventional veterinary community are working hard to convince pet parents that processed so-called therapeutic or prescription diets are "food as medicine" and the wave of the future.1

I think fresh food diets made with human-grade human ingredients designed for dogs with specific health conditions are a great idea (more about this shortly). Unfortunately, what you get with a processed prescription diet is simply a modified version of the same feed-grade ingredients found in nonprescription pet food.

In my experience and that of other integrative veterinarians, highly processed diets made with feed-grade ingredients (and the toxins that come along with feed-grade ingredients) are the root cause of many of the diseases pets acquire today. It's reprehensible that when dogs become sick with degenerative diseases after years of eating processed, biologically inappropriate food, their owners are told to buy a more expensive version of a similar food and consider it "medicine."

Conceptually, feeding recipes that have low oxalates, modulate urine pH, have reduced copper or iodine, or address a specific nutritional goal is wonderful advice.

The problem is, there's not a single brand of dry or canned food that uses human-grade ingredients. Because the FDA allows "animals that have died otherwise than slaughter" in pet food, and no heavy metal or contaminant testing is required for therapeutic foods purchased only through veterinarians, the quality of the raw materials going into "prescription diets" is questionable, at best.

Why processed 'prescription' diets aren't good medicine

The information in the chart below is an example of what I'm talking about. It's a comparison of the first 10 ingredients in a regular Hill's diet and a Prescription diet. The no-prescription diet on the left claims to improve skin and coat in 30 days. The prescription diet on the right is marketed as for dogs with skin and food sensitivities.

Hill's® Science Diet® Adult Advanced Fitness Original Dog Food2 Hill's® Prescription Diet® d/d® Canine Skin Support Potato & Salmon Formula3



Whole grain wheat

Potato starch

Cracked pearled barley


Whole grain sorghum

Potato protein

Whole grain corn

Pork fat

Corn gluten meal

Soybean oil

Chicken meal

Pork flavor

Pork fat

Dicalcium phosphate

Chicken liver flavor

Lactic acid

Dried beet pulp

Fish oil

Note the inferior-quality, biologically inappropriate ingredients in both these dog foods, such as multiple potato products, grains, corn, and questionable fats and oils. The diet on the right, the so-called "food as medicine" diet, is what the pet food industry and many veterinarians would have you feed a dog dealing with skin problems and food sensitivities, both of which are often the result of eating a diet like the one on the left.

It's foolish to think we can feed pets biologically inappropriate convenience food every day for years and then when health problems arise, treat them with a different version of a similar poor-quality diet. None of the processed prescription or therapeutic diets currently on the market are made with human-grade ingredients nor contain any ingredients that qualify them as needing a prescription; it's a marketing strategy.

Your veterinarian may not be a good pet nutrition resource

If your veterinarian recommends a therapeutic or prescription diet for your dog, I encourage you to ask him or her to help you create balanced, homemade, customized recipes using a tool like the Animal Diet Formulator. Alternatively, you might consider Darwin's Intelligent Design™ Veterinary Formulas that actually do contain beneficial nutraceuticals for specific medical conditions.

Otherwise, you'll be spending a lot of money for poor-quality pet food that won't improve your furry family member's health in the long run. Holistic and integrative veterinarians are often much more knowledgeable about the role nutrition plays in an animal's healing response than conventional practitioners who haven't studied the subject beyond what they learned in vet school (which was minimal, and typically taught by pet food industry reps).

Unfortunately, even the majority of board-certified veterinary nutritionists have also been schooled primarily about processed pet diets, and believe it or not, major pet food manufacturers frequently pay the tuition for DVMs studying to become veterinary nutritionists.

The ACVN (American College of Veterinary Nutrition) is the smallest of the veterinary colleges and there are relatively few veterinary nutritionists in the world. They work in veterinary schools, government agencies, pet drug companies, private animal hospitals, for themselves, and very frequently, for pet food companies.

So when a veterinary nutritionist recommends X, Y or Z food — or discourages feeding raw or homemade diets, which is common — keep in mind that many practicing veterinary nutritionists are obligated in some way to a pet food manufacturer. Strangely, the vast majority of these extensively trained nutritionists advocate for the consumption of only processed food for a pet's entire life. In fact, they caution that feeding anything except shelf-stable pellets may be dangerous to your pet's health.

Sadly, for most board-certified nutritionists, their association with a major pet food company creates an obvious conflict of interest when it comes to the advice they offer, which is typically to encourage pet owners to stick with big-name processed pet foods for the lifelong "health" of their four-legged family members.

Choosing the right nutrition for your dog

If you're wondering what diet would be best for your own pet and don't find your current veterinarian's suggestions helpful, I encourage you to try to find an integrative or holistic vet in your area (or via phone consultation) who is knowledgeable about animal nutrition. These vets, who've studied animal nutrition outside the conventional realm, can work with you to customize a balanced, species-appropriate diet to address the specific health needs of your animal.

The goal is to create a diet and supplement protocol based on your pet's individual and dynamically changing needs — a diet that mimics your pet's ancestral diet as closely as possible, but also stays within the nutritional and metabolic parameters that can set the stage for disease recovery or prevention. This is how food truly becomes medicine.

My standard recommendation is to feed your pet as much unprocessed, fresh food as you can afford, which can be tailored to address specific medical needs. Depending on your pet's medical condition, which will dictate which ingredients are selected for creating a nutritionally balanced recipe, this could be an all-fresh, living, raw food diet, or a gently cooked diet.