What's Up Doc?

Do New Trend Diets = Better Nutrition?

By Maury Docton, DVM

Many of the new “trendy” diets contain a broad array of vegetables, fruits, Prebiotics (fibers), Probiotics (helpful bacteria), and other ingredients promoted as beneficial or “functional.” It is important to remember that a manufacturer may add these ingredients with good intentions for benefiting the dog or cat but, may not have any research or proof to support the use of these ingredients. For example, with respect to Probiotics, under the current methods of producing pet food, the cooking process in extrusion kills most, if not all, bacteria – desirable forms as well as undesirable; this would make the benefits of most helpful bacteria minimal, except for providing a small amount of extra protein in the form of dead bacteria.

There is limited evidence that the inclusion of fruits and vegetables in the food provides any benefit other than additional fiber and starch. According to Dr Greg Aldrich, a nutrition consultant and contributing author for Pet Food Magazine, “From a regulatory perspective, it is easier to make a claim about the ingredients used in the product than about whether they have an impact on the animal. One lets the consumer make that connection.” In other words because an ingredient is included, doesn’t mean it will ulti mately benefit the animal.

Actual nutritional research provides the proof that an ingredi ent benefits the pet; that is how we are able to make claims like “Smarter, More Trainable” and “Reduces Tartar in the dog by 55%.” Whatever ingredients are included in a pet food formula directly impact the overall nutrition provided to the pet. This is noteworthy because the inclusion of blueberries, carrots, spinach, etc. primarily provide carbohydrates – both fiber and starch. There are only three sources of energy in food; protein, fat, and starch; if a diet is high in starch, then fat and protein must be reduced or the diet will be very high in calories. As an example, analyzing one of the new “Holistic” diets reveals that 5 of the first 7 ingredients are carbohydrates; this drops the protein to 22% and the fat to 12%. As a comparison, Eukanuba Adult Maintenance provides protein at 25% and fat at 16% with almost exactly the same calories per cup1. This translates into lower carbohydrates in the Eukanuba diet; this is important because dogs and cats need protein for tissue repair and maintenance and they preferentially use fat for energy – they are designed to function best on fat for energy. P&G Pet Care designs foods that function to enhance the well-being of dogs and cats. Trend and boutique diets are often designed to provide nutrients that the owners of the pets would like, forgetting that dogs and cats are not little people in fur coats.

“From a regulatory perspective, it is easier to make a claim about the ingredients used in the product than about whether they have an impact on the animal.”
Dr. Greg Aldrich, Pet Food Magazine

Consider This

Much has been said recently in advertising “Grain-free” diets. Grains, such as wheat, rice, and corn, have been portrayed in a negative light.

UNTRUTH Corn is not digestible... Corn causes allergies … Dogs and cats don’t have the ability to digest grains

THE TRUTH is that, although there are individual variations, ground corn is less than 2% fiber; therefore, 98% digestible.

The only part of an ingredient that can trigger an allergy is the protein portion of that ingredient; unless corn is used as a protein, in its gluten form, it is very unlikely to trigger an allergic reaction – corn meal contains less than 8% protein. Beef, wheat, & dairy proteins are responsible for 70% of all food related allergies. Fruits and vegetables are providing the same carbohydrate function as grains, but without research documentation to prove how they affect the energy level and glycemic response of the pet.

Through extensive research, P&G Pet Care has documented an effect similar in principle to the South Beach Diet. This graph represents the effect that various starch sources can have on blood sugar after an animal eats.

  • After a meal, starch sources are broken down by the body into glucose (sugar), which is absorbed into the blood stream and supplies energy for the body’s cells
  • The type of starch consumed can affect how fast blood glucose rises in the blood stream
  • Blood glucose levels affect appetite and energy
  • Rice is most quickly converted to glucose. Sorghum is the slowest.

It is important to understand the purpose of a diet when analyzing carbohydrates because types of carbohydrates can influence energy levels and appetite.

  • Animals eat to feed their energy needs.
  • A mix of selected carbohydrates can address the nutrition needs of different life stages.


1 Euk-403/ “Holistic diet A”-407.