Myths (and Truths) About Grains in Pet Food

by Linda L.

“What is the best food to feed my pet?”

This is one of the most common questions posed to our veterinarians here at Family Pet Animal Hospital. Answering this question has certainly become more complicated than it once was.  Good nutrition for your pet means feeding him or her food that provides the building blocks and energy components that allow him/her to grow, develop properly, and remain healthy and active throughout his or her lifetime. Because every pet is unique, there is no cookie-cutter, one-size-fits-all answer to this question. The goal is to find the right food for your pet that is nutritionally balanced to produce optimal health.

Navigating through the abundance of information and misinformation, deciphering cryptic pet food labels, and being constantly inundated with food manufacturers’ marketing buzz words can create a lot of confusion. It is important to think of food in terms of providing the energy, vitamins, and minerals necessary for normal body functioning.  Energy comes from proteins, fats, and carbohydrates. In recent years, grains, especially corn, have developed a bad rap. Is there any truth in the claim that a grain-free diet is best for your pet?  We’re here to debunk some of the most common myths about grains (and other ingredients) in pet food so you can make more informed decisions about what to feed your pet.

According to Jennifer Larsen, DVM, PhD, DACVN, an associate professor of clinical nutrition at the Veterinary Medical Teaching Hospital at the University of California Davis, “Grains, and any other single category or individual ingredients, are neither good nor bad.  Rather, what is important is how the ingredients work together to create the full nutritional profile of the diet.  Likewise, carbohydrates, as an energy source, are utilized by the body the same way regardless of source, such as grain, legume, or tubers, and different sources of carbohydrates also bring other nutrients, such as fiber, fatty acids, and amino acids.  Again, no ingredient has a simple effect since each provides multiple nutrients, and it’s not consumed in a vacuum.”

Let’s talk about the most common MYTHS and TRUTHS about grains (and other controversial ingredients) in pet food.

 

Myth vs Fact - Grains in Pet Food (1)

 

Myth #1:  Dogs and cats did not evolve eating grains and therefore cannot digest them

“In fact, modern dogs have adapted/evolved eating a high starch diet during their domestication,” says Rebecca Remillard, PhD, DVM, DACVN, the founder and president of Veterinary Nutritional Consultations, Inc.  She cites a 2013 study reported in the journal Nature, which states that in a comparison of a domestic dog’s genome versus a wolf’s, the three genes responsible for the digestion of dietary starch were expressed 7-12 fold higher in the dog.  Remillard adds, “…digestibility studies published in the Journal of Animal Physiology and Animal Nutrition … have clearly demonstrated that both dogs and cats digest better than 95% of the starch in a properly cooked diet containing 50% corn or rice.”

Ann Wortinger BIS, LVT, VTS, is a veterinary nutritionist who has worked in the field for over 20 years.  She notes that with any grain, “when higher levels are included in the diet, protein digestibility can go down… All plants, due to their cellulose layers, have decreased digestibility when compared to meats.  But when ground and cooked, so that the cellulose layer is broken, digestibility is comparable [to meat].”

Myth #2:  Grains are responsible for pet allergies

Despite frequent claims to the contrary, meat ingredients are the more common culprit of food allergies than grains. There is no current evidence to support that pets on grain-free diets have lower incidence of food allergies than pets on conventional diets.  Larsen adds, “… to my knowledge, there is no inherent characteristic of any particular grain that would make it more likely to elicit an immune response.” She states that historically, the most common allergens for dogs and cats are beef and dairy.  While she suspects that this may be changing due to ingredient trends, no change has been recently reported in scientific literature.

While some dogs do have allergies to wheat, Celiac disease (allergy to wheat gluten) is very rare in pets and has primarily been reported in the Irish Setter breed.  Wheat gluten is more than 80% protein, highly digestible, has an amino acid profile similar to other proteins (meat), and enhances the texture of food.  Anyone who has a pet that is a finicky eater can tell you that last one can be a top priority.

Myth #3:  You can determine the quality of a pet food by reading the ingredient list

Remillard says, “Despite aggressive marketing campaigns by various manufacturers and self-appointed websites, the ingredient list according to the Association of American Feed Control Officials (AAFCO) should not impart any information regarding the quality, nutritional balance, or digestibility of the pet food product… The ingredient list was simply not designed, or is not regulated, as a measure of pet food quality.  So the source of the meat or carbohydrates in a pet food is not important to the nutritional profile in a complete and balanced product.”

Does your pet food boast the labels “all natural,” “holistic,” or “human-grade”?  According to AAFCO, the term “natural” requires a pet food to consist of only ingredients that have not been subjected to chemical synthesis.  There are no legal definitions of the terms “holistic” or “human-grade,” therefore under pet food laws, anyone can claim these terms for their food.  These terms may sound appealing but are, in fact, meaningless.

Are all “by-products” bad?  Not at all, in fact, we eat them!  By definition and regulation, by-products are the non-meat parts of chicken, beef, pork, etc. after the meat has been removed.  However, by-products are NOT feathers, beaks, fur hooves, or teeth.  Examples include animal fats and clean internal organs – pork, chicken, and beef liver, heart and kidneys.  All these items have nutritious value and are often preferred over muscle meat by animals.  Other examples are treats we commonly give our pets – bully sticks, raw hides, pig’s ears, cow hooves, trachea, and lamb lung.  By-products are a valuable source of energy, vitamins, and minerals.  And while it may sound good to feed your pet a meat-only diet, muscle meat alone is deficient in many nutrients, which could lead to poor growth, bone fractures, and loose teeth.

Is whole meat better than meat meal?  Here are the AAFCO definitions of what constitutes “meats” and “meals.”

  • Meat – “Meat is the clean flesh derived from slaughtered mammals and is limited to that part of the striate muscle which is skeletal or that which is found in the tongue, in the diaphragm, in the heart, or in the esophagus; with or without the accompanying and overlying fat and the portions of the skin, sinew, nerve, and blood vessels which normally accompany the flesh. It shall be suitable for use in animal food. If it bears a name descriptive of its kind, it must correspond thereto.”
  • Meat meal – “Meat meal is the rendered product from mammal tissues, exclusive of any added blood, hair, hoof, horn, hide trimmings, manure, stomach and rumen contents except in such amounts as may occur unavoidably in good processing practices. It shall not contain added extraneous materials not provided for by this definition…. If the product bears a name descriptive of its kind, composition or origin, it must correspond thereto.”

As with all ingredients, if the meat is from a well-known provider and is of good quality, it can be an excellent source of protein.  According to “Myths and Misconceptions Surrounding Pet Foods” on the Ohio State University Veterinary Medical Center’s website, “Because of the variation in meal content, and in meat and meal quality, purchasing a food from a well-known company who stands behind their product and has the feeding trials and evidence to support its quality is best.”

We recommend that you look at the nutrients rather than the ingredients in foods.  According to Wortinger, “The body does not care if the meat is chicken, beef, or reindeer; what is cares about is the amino acids included in the food.  The body does not care whether the fat is animal or plant-based, but whether all the essential fatty acids are present.  Look at nutrients, not marketing.”

Myth #4:  Grains are non-nutritive fillers

“I’ve heard concerns about them [grains] being ‘filler,’ which is nonsense,” Larsen says.  Grains are added because they are a good source of carbohydrates, which are essential for growth in puppies and kittens and are an important source of energy for most cells of the body (young or adult).  Corn and wheat, two common grains found in pet foods, are excellent sources of quality protein, vitamins, minerals, essential fatty acids, and antioxidants.  Corn meal, which commonly appears in a list of pet food ingredients, is simply corn minus the water and fat and is highly digestible.  Properly processed and cooked grains are generally well-utilized by both cats and dogs.  Furthermore, the fiber provided by grains is essential for the health of the gastrointestinal tract.

Martha G. Cline, DVM, DACVN, is a clinical veterinary nutritionist at AAHA-accredited Red Bank Veterinary Hospital in Tinton Fall, N.J.  She states, “Although fiber is not a required nutrient, I find that it can be very beneficial in optimizing the stool quality and the overall health of my patients.   Grain-free diets can provide optimal nutrition for cats and dogs, however, diets containing grain can do the same.”

Now What?

We’ve debunked some of the biggest myths about grains and ingredient lists, but you’re still asking, “What should I feed my pet?”    There is no “best” food for all pets because of each pet’s unique factors that determine what is “best” – life stage, body condition, level of exercise, environment, and health status.  The most important considerations are if the food is nutritionally adequate and if your pet is healthy when you feed him or her that food.

All pet food labels in the United States must include the AAFCO adequacy statement.  This statement confirms whether the diet is complete and balanced, for which life stage the food is intended, and how the food company determined that the food is complete and balanced (recipe or analytic testing of the finished product; or feeding trials).  If you are home-cooking your pet’s food, then a diet formulated by a board-certified veterinary nutritionist is recommended so that the food isn’t nutritionally deficient.

Raw diets, produced to supposedly mimic what cats and dogs eat in the wild, have become increasingly popular.  Generally, these raw diets consist of variable combinations of raw meats, grains, vegetables, and bones.  As with grain-free diets, there is no scientific evidence that feeding a raw versus conventional diet is advantageous to your pet’s health.  While we recognize the desire for some people to feed a raw diet to their pets, we stress the importance of understanding the risks.  Raw diets are much more likely to be contaminated with disease-causing bacteria, such as Salmonella and Listeria monocytogenes.  Exposure to these pathogens has the potential to cause serious illness in both pets and humans.  If you have a household with very young, old, or immunocompromised inhabitants, the risks are even greater.  Anyone feeding a raw diet should follow strict handling guidelines such as these outlined by the FDA:  http://www.fda.gov/AboutFDA/Transparency/Basics/ucm206814.htm

In summary, no matter how good the company, how pretty the packaging, how yummy sounding the ingredients, the only TRUE test of whether a food is good for your dog or cat is what happens when you feed it.  Don’t let your decisions about pet food be based on marketing messages instead of objective nutritional data.

Additional Resources

Pet Nutrition – Separating Fact from Fiction

Pet Nutritional Counseling

Searchable Pet Health Articles Database

Sources:

Smith, Kelly. “Myth Busters: Corn Edition!” NEWStat. American Animal Hospital Assocation, 17 Jan. 2017. Web. 25 Jan. 2017.

Freeman, Lisa M., DVM, PhD, DACVN. “Pet Food Myth Busters: Answering Common Questions Owners Ask About Pet Food.” (n.d.): n. pag. Clinician’s Brief. 2015. Web. 25 Jan. 2017. <http://www.cliniciansbrief.com/sites/default/files/attachments/Pet%20Food%20Myth%20Busters.pdf>.

“Myths and Misconceptions Surrounding Pet Foods.” The Ohio State University Veterinary Medical Center. N.p., n.d. Web. 25 Jan. 2017.