By Dr. Becker
I ran across a pet food industry article recently in which a DVM (but not a board-certified nutritionist, in this case) was dispelling pet food ingredient “myths.” From my perspective, the guidance this veterinarian is providing to correct so-called misguided information floating around the Internet demands a closer look.
“By-products are nutrient rich organ meats…”
The first “myth” Dr. Trish Kirby discusses is the tendency of increasing numbers of pet owners to avoid pet foods containing by-products. Dr. Kirby states, “By-products are nutrient-rich organ meats that may contain a better quality protein than other muscle meats.”
Let’s compare Dr. Kirby’s definition of by-products with AAFCO’s definition of chicken by-product meal:
Chicken by-product meal consists of the dry, ground, rendered, clean parts of the carcass of slaughtered chicken, such as necks, feet, undeveloped eggs and intestines -- exclusive of feathers except in such amounts as might occur unavoidable in good processing practices.
… or how about AAFCO’s definition of meat by-products:
Meat by-products consist of the non-rendered, clean parts, other than meat, derived from slaughtered mammals. It includes, but is not limited to, lungs, spleen, kidneys, brain, livers, blood, bone, partially defatted low-temperature fatty tissue and stomachs and intestines freed of their contents. It does not include hair, horns, teeth and hooves.
Clearly, all by-products are not “nutrient-rich organ meats” as Dr. Kirby stated. By-products are the remains of an animal carcass after the parts approved for human consumption have been removed.
If you buy a pet food containing by-products, you might luck out once in awhile and get a mixture containing primarily organ meats – livers and hearts, for example -- that are adequately digestible and nutritious. However, it’s more likely you’ll get an ingredient mixture containing few nutritious organ meats, and plenty of hard to digest pieces-and-parts of carcass remains. That’s one of the essential problems with by-products – the nutrition value and digestibility of ingredients can’t be counted on from one ingredient batch to the next.
And let’s face it, if by-products consisted exclusively of nutrient-rich organ meats with better quality protein than muscle meats, pet food companies would have long ago figured out how to market them accordingly.
For much more information on organ meats in pet food, read my article titled The Best Way to Provide Organ Meats to Your Pet.
“Corn is a nutritional grain …”
Another supposedly misguided belief among pet owners is that corn is a non-nutritious filler found in cheap pet foods.
According to Dr. Kirby, this is incorrect, and instead:
“Corn is a nutritional grain that provides your pet with needed protein and carbohydrates. It contains antioxidants such as beta-carotene and vitamin E, as well as essential fatty acids that keep the skin and fur healthy.”
Corn is a plant, so the protein it provides to carnivores is suboptimal. Meat proteins closely resemble the essential amino acid requirements of dogs and cats – plant proteins do not. Meat proteins easily provide essential nutrients to your pet – plant proteins, including corn, simply do not.
With regard to your pet’s carbohydrate needs … if you have a cat, his body isn’t even designed to digest carbohydrates. It lacks the salivary, intestinal and pancreatic enzyme activity necessary to break down and digest carbs. Your dog’s body can process a certain amount of carbohydrates efficiently – primarily those from dark green veggies. Corn as a carbohydrate has a relatively high glycemic index and a relatively low biologic value (lower, even, than wheat).
The nutritional value of corn (antioxidants and such) is also relatively low. The Nutrient Balance Completeness Score measures foods for their vitamin, mineral and dietary fiber content. Spinach scores 91, sweet potatoes 55, and corn, 34.
More bad news about corn
Unless corn is heavily processed into meal or flour form and then cooked, it is extremely difficult for your pet to digest. Most corns and other grains are, in fact, digestible only IF they are heavily processed. The finer the corn is ground, the more digestible it will be, but the higher its glycemic index.
Let’s also not forget that corn is allergenic. While there is little “scientific” evidence to back up this fact, there is plenty of empirical evidence offered by countless pet owners and vets of the improvement in an animal’s health when transitioned away from a food containing corn products.
Corn is also the number one crop infected with deadly aflatoxins, and even more alarming is that weather conditions during the summer of 2012 in the U.S. were ideal for the growth of two types of molds that infiltrate corn plants and produce aflatoxins.
And then, of course, there’s the issue of genetically modified corn crops. This means the seeds have been chemically altered to produce plants that can withstand repeated spraying with Monsanto's Roundup weed killer. Estimates are that over 60 percent of corn grown in the U.S. is genetically modified, and half the sweet corn grown on U.S. farms comes from genetically modified seed.
“Raw food diets are rarely nutritionally balanced …”
Not surprisingly, Dr. Kirby also cautions against raw pet food by stating that:
“Raw food diets (BARF diets) are rarely nutritionally balanced and often don't meet all of our pets' needs in terms of vitamins and minerals.”
As I often point out both here at Mercola Healthy Pets and to clients at my practice, there’s nothing worse for your pet from a nutrition standpoint than an unbalanced diet, raw or cooked, homemade or store bought.
But Dr. Kirby’s assertion that raw food diets are “rarely” nutritionally balanced is simply not true. There are several high quality commercial complete and balanced raw pet food diets available on the market today. There are also several websites and books in existence, including my own book, with recipes for preparing nutritionally balanced homemade pet food. It’s a matter of understanding and providing for the nutritional needs of your dog or cat, whether you prepare the food yourself or buy it ready to serve.
Dr. Kirby also states, “More important, raw diets can be contaminated with dangerous bacteria such as salmonella and E. coli, which can cause serious gastrointestinal disease in both humans and animals.”
This is, of course, parroting the AVMA’s position statement on raw pet food diets, which I discussed and discredited in an article in July of last year, and another in September.
Why, suddenly, is all this bad nutrition advice floating around?
It’s really quite discouraging to see a flood of veterinarians recently – including board-certified nutritionists – publicly stating that grain, gluten, corn and by-products are desirable ingredients in pet food … that raw diets are dangerous … that pet owners should stick with low quality, highly processed formulas produced by the biggest players in the pet food manufacturing industry.
I honestly can’t say what’s behind this sudden influx of really bad nutrition advice coming from the traditional veterinary community. All I can do is challenge it as I become aware of it.
If you have questions about your own pet’s diet, I encourage you to talk with a holistic vet about species-appropriate nutrition for your dog or cat. I also recommend you do research on your own so that you’ll be equipped to make good choices in your pet food purchases, or in selecting ingredients to make your pet’s food at home.