Don't Expect Your Pet to Weather This Choice of Pet Food Well

Written by Dr. Karen Shaw Becker

species appropriate diet for pets

Story at-a-glance -

  • The processed pet food industry wants you to believe “carbs are good” for dogs and cats and that its “scientific data” doesn’t support the notion that grain-free is better than grains
  • Missing entirely from this and all similar “scientific data” is the nutrition dogs and cats evolved to eat, also known as their ancestral diet, or the fact that as carnivores, they have no nutritional requirement for carbs
  • If you feed kibble, it’s important to find out how much carb content the food contains, as typically it will be many times the maximum recommended amount
  • There are many other reasons to avoid feeding kibble, including the dubious quality of raw ingredients, the potential for cancer-causing byproducts and the lack of moisture
  • The best diet for dogs and cats is nutritionally balanced, species-appropriate, and grain and carb-free

There’s a blogger for a pet food industry journal who’s working hard at “debunking pet food myths and misconceptions.” His background includes spending “multiple years developing, formulating and launching dog and cat foods as a senior executive with leading pet food companies.” The guy is clearly as passionate about feeding processed pet food as I am about avoiding it.

He tends to write mildly outrageous headlines for his blog posts, such as this one: “Why grain-free pet food isn’t better and carbs are good.”1 In the article, he focuses on extruded kibble “since this category makes up most of the pet food products in the marketplace today.” Sadly, he’s right about that. Way too many dogs and cats are still eating a junk food diet every day of their lives.

The point of his article, I think, is to make the case that grain-free formulas aren’t free of starches or carbohydrates (which is true), and that dogs and cats digest all forms of extruded starch, including grains, similarly. Therefore, he concludes, “The scientific data does not support the notion that grain free is better than grains.”

Conveniently missing from this blog post and all pet food industry articles touting the virtues of kibble is any mention of the ancestral diet of dogs and cats, which should be (but certainly isn’t) the foundational “scientific data” that is used to formulate pet diets.

Your Pet's Ancestral Diet

First and foremost, when deciding what to feed your dog or cat, it's important to remember that your pet is a carnivore. His genetic makeup and internal workings remain essentially the same as his wild carnivorous ancestors.

The ancestral diet of a carnivore includes lots of variety and seasonal variability because certain prey is more available at certain times of the year. Wild dogs and cats thrive by consuming fresh, living whole foods. The food is moisture-dense because prey animals are about 70 percent water, plus it's high in animal protein and minerals, and moderate in fat.

There are no obese rabbits or other small prey animals in the wild, which is why dogs and cats do best with a diet that contains moderate to low amounts of high-quality animal fat and a very low percentage of carbohydrates. The only carbs wild cats consume are what is naturally found in the gastrointestinal (GI) tracts of their prey, plus the occasional nibble of grass which provides added fiber and enzymes.

Wild dogs (including wolves) are facultative or scavenging carnivores, so their diets are more varied than wild cats. Like cats, they catch, kill and consume whole prey, but unlike cats, they also eat carrion (dead animals). Wild dogs also eat poop, grass, berries and other plant matter. In fact, research shows that up to 30 percent of the stomach contents of wolves contain plant matter.

No, Carbs Are NOT Good Nutrition for Dogs and Cats, and It’s Irresponsible to Claim Otherwise

The notion that carbohydrates are a biologically correct source of energy for dogs, and especially cats, is nonsense. Fat is nature’s very best energy source for carnivores, who actually have no carbohydrate requirement.

Contrary to what the pet food industry wants us to believe, carbohydrates are not a “main macronutrient” required by dogs and cats. Neither the Association of American Feed Control Officials (AAFCO) nor the European Pet Food Industry Federation (FEDIAF) stipulates a requirement for carbohydrates in pet food, because again, dogs and cats have no nutritional requirement for carbohydrates.

The fact is, calories from starchy carbohydrates should be less than 10 percent of the total calories consumed by your pet each day. The carb content of processed pet food, especially grain-free formulas, is typically many times the amount pets require.

The starch in these foods is converted to sugar. I believe one of the biggest reasons we are seeing an epidemic of metabolic and inflammatory diseases in pets is because of the unnaturally high amounts of starch (sugar) in processed pet foods we’ve fed our pets over the last 50 years.

How to Determine the Carb Content of Kibble

To determine what percentage of the food you’re feeding your dog or cat is made up of carbohydrates, find the “guaranteed analysis” on the bag and apply the following formula:

100% - % protein - % fat - % moisture - % ash (if not listed, use 6 percent)
= % carbs

Fiber is indigestible roughage that doesn't break down into sugar, so you don't have to include it in the formula.

Example, cat food: Royal Canin Indoor Adult Dry Cat Food

100% – 27% protein – 15% fat – 8% moisture – 6% ash = 44% carbs

Example, dog food: Royal Canin Medium Adult Dry Dog Food 

100% – 23% protein – 12% fat – 10% moisture – 6% ash = 49% carbs

In both these examples, the amount of carbohydrates far exceeds the amount a cat or dog is able to effectively digest and assimilate. And believe it or not, most grain-free dry formulas are even higher in carbs than regular formulas like the Royal Canin products.

If you're feeding a dry diet, it might be free of grains, but it can't be free of carbs, because carbs are necessary to form kibble. If you look at the package label, you'll see potato, sweet potato, lentils, peas (pea starch), chickpeas, tapioca or another carbohydrate source(s).

Carb-heavy pet food can lead to blood sugar fluctuations, insulin resistance, obesity, diabetes and other health problems in pets. Carb intake above your dog’s or cat’s daily needs triggers internal enzyme factors to store the excess as body fat.

Carbs Aren’t the Only Problem With Kibble

While most kibble is formulated to meet the basic nutritional requirements of dogs and cats, it certainly doesn’t provide optimal nourishment for the long haul. I have several issues with dry pet food, starting with the quality of the raw ingredients.

Rendering plants create meat and bone meal from a variety of dubious sources, for example, parts of cows that can't be sold for human consumption, including bones, the digestive system, the brain, udders, hide and more. The vast majority of pet foods are made with ingredients rejected by the human food industry, meaning they’re feed-grade.

They also may use the carcasses of diseased animals, expired grocery store meat (including the plastic and Styrofoam packaging), road kill, zoo animals and dogs and cats that have been euthanized. Here’s a stomach-turning description of the process of spinning these raw ingredients into pet food from Slate:

"This material is slowly pulverized into one big blend of dead stuff and meat packaging. It is then transferred into a vat where it is heated for hours to between 220 [to] 270 degrees F. At such high temperatures, the fat and grease float to the top along with any fat-soluble compounds or solids that get mixed up with them.

Most viruses and bacteria are killed. The fat can then be skimmed off, packaged and renamed. Most of this material is called 'meat and bone meal.' It can be used in livestock feed, pet food or fertilizer … There is essentially no federal enforcement of standards for the contents of pet food.

… Indeed, the same system that doesn't know whether its main ingredient is chicken beaks or Dachshund really cannot guarantee adequate nutrition to the dogs that eat it."2

The majority of dry pet food is a blend of poor-quality meats, byproducts and synthetic vitamins and minerals. In addition, most kibble contains high-glycemic, genetically engineered (GE) corn, wheat, rice or potato — grains and starches that have no place in a carnivore’s diet and create metabolically stressful insulin, glucagon and cortisol spikes throughout the day.

In the last 50 years, we've learned the hard way that feeding nutritionally unbalanced, biologically inappropriate diets to pets does not create health. In fact, chronic inflammatory and degenerative diseases in dogs and cats are at epidemic levels, and the problem can be traced directly to diet and lifestyle.

To make matters worse, the poor-quality proteins and fats used in most kibble, when processed at high temperatures, create cancerous byproducts such as heterocyclic amines. The meat that goes into dry pet food is put through at least four high-temperature cooking processes, leaving the digestibility, absorbability and overall nutrient value highly questionable.

The low moisture content of dry food is also problematic, especially for cats. Dry cat food provides only about one-tenth the amount of moisture cats receive from prey animals, living foods and even commercial canned diets, which puts significant stress on their kidneys and bladder. Dogs also tend to become excessively thirsty when fed a dry diet.

My Recommendation: Feed Your Pet a Grain- and Starch-Free Species-Appropriate Diet

Feeding a species-appropriate diet means the food you offer your pet:

  • Is grain-free and carb-free — no corn, no wheat, no rice, no millet, no oatmeal, no potato, no sweet potato, no tapioca, no peas, etc.
  • Is in its biologically correct form — raw, whole, unadulterated and undenatured meat
  • Contains all the moisture needed for your pet's body to process the food with very little metabolic stress

My first recommendation is to feed a raw-food diet. It's grain-free, moisture-rich, living, and of course, fresh. My alternative recommendation is canned food or a gently dehydrated (air-dried) raw food that can be reconstituted with water to contain at least 70 percent moisture. For additional recommendations, read “From Best to Worst — My New Rankings of 13 Pet Foods.”

The difference between air dehydrated foods and extruded foods is temperature. Foods that aren’t cooked or extruded at high temperatures retain more nutritional value. When air-dried foods are reconstituted with water, they also become moisture-rich and significantly healthier than any dry kibble on the market.

Also check with the pet food manufacturer to make sure whatever food you choose is nutritionally balanced. Many of the new niche pet foods appearing on store shelves are intended for intermittent feeding only — it should say that on the label. This means the formula doesn't meet AAFCO standards for a complete and balanced pet food, and must be fed in rotation with other nutritionally complete foods to create a balanced diet for your furry companion.