Are Expensive Pet Foods Healthier Than Cheap Ones?
Pet food aisles are full of packages that claim to hold “natural” and “holistic” foods, with pictures of fresh vegetables and roast chicken on the front. But there’s not much difference between these foods and the cheapest by-product-filled kibble. Here’s what you can expect to find in your pet’s food.
What Does “Chicken” Mean, Exactly?
Dogs and cats both love to eat meat, and their wild relatives happily snarf down smaller creatures, often organs and all. So pet foods should, and do, usually contain plenty of animal tissue. But if you’re envisioning filet mignon—or even those chunks of lean chicken and salmon that grace package labels—you’re not thinking like your pet.
“If you buy commercial pet foods at all, you are buying ingredients that humans do not want to eat,” Marion Nestle and Malden Nesheim write in Feed Your Pet Right, a great read if you want to know what’s really in your pet’s food. That doesn’t mean there’s anything wrong with what we feed our pets—after 300 pages of analysis they conclude that all the commercial foods are basically fine—but most of the meaty ingredients are things you would never see in a grocery store.
Take beef, for example. The Association of American Feed Control Officials defines it as “the clean flesh derived from slaughtered mammals and is limited to that part of the striate muscle which is skeletal or that part 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 portions of the skin, sinew, nerve, and blood vessels which normally accompany the flesh.” Poultry has a similar definition, but it may include ground-up bone.
There’s no need to slaughter food animals just to make pet food, since the meat industry has plenty of scraps that you and I aren’t interested in buying. So if your dog food boasts “chicken” as the number one ingredient, you’re probably getting a slurry of meat, skin, and gristle that was mechanically separated from leftover chicken necks and backs. It’s nutritious and delicious, if you’re a dog.
Here are a few other meat-related terms you’re likely to see on pet food labels:
By-products include clean parts of slaughtered animals that are edible to animals but don’t count as meat. These might be beef lungs, spleen, kidneys, brain, liver, blood, bone, and fat. For poultry, by-products can include heads and feet.
Meals, like “chicken meal” or “fish meal”, are rendered. This means the producers take edible parts—either meat or by-products—and cook and dry them into a powder.
What Else Is In There Besides Meat?
Plenty of pet food brands boast meat (or something like it, like “chicken”) as their number one ingredient. That’s fine, but no matter how the ingredients are ordered, there are almost always grains, vegetables, and other components like vitamins and minerals.
You can tell from the phrasing on the package just how much meat is in the product. The AAFCO sets minimum percentages for any meat the label plays up:
100 percent chicken means literally that: a food that is made entirely of chicken. (These are rare—but remember, again, that this can include mechanically deboned chicken slurry.)
Chicken dog food must be at least 95 percent chicken, or 70 percent if it’s a wet food (since the water makes up part of the food’s weight).
Chicken recipe implies that chicken is part of the food, but that there are other ingredients. To use wording like this, the food has to be at least 25 percent chicken (or 10 percent if it’s a wet food).
Made with real chicken means it must contain at least 3 percent chicken.
Chicken flavor doesn’t require a minimum amount of chicken, as long it’s somewhere in the ingredient list. The same goes for “meaty”—you can use that word on any pet food that contains meat. Sometimes these flavoring ingredients are sprayed on the outside of the kibble.
As a rule of thumb, salt is somewhere around one percent of a pet food. So anything that appears after salt in the list is only present in trace amounts. That’s sometimes the case for fruits and vegetables pictured on labels.
In their book, Nestle and Nesheim were able to rule out some of the things that aren’t in pet food. For example, none of the by-products include hair, horns, teeth, or hooves. And despite rumors, you won’t find wood shavings, motor oil, or old boots in pet food, either. (There is an ingredient definition on the books for “hydrolyzed leather meal,” which can be made by cooking and processing leather scraps, but nobody uses it; Nestle and Nesheim write that they “doubt state feed control officials would allow it.”
On the other hand, they tried to track down what happens to dogs and cats that are euthanized at shelters, and found that they sometimes end up at the same rendering plants that supply ingredients for pet foods. Traces of euthanasia drugs have been found in pet food samples, but at very low levels. This doesn’t seem likely to be a widespread practice, but worryingly, neither Nestle and Nesheim nor Snopes have been able to confirm or deny whether it happens occasionally.
Are the Non-Meat Ingredients a Problem?
Nutritionally, pets need the vitamins and other nutrients that come from unappetizing places like prey animals’ organs and stomach contents. Cats and dogs have also adapted to scrounging food from our plates and our garbage dumps, so it makes sense that their diets wouldn’t be the same as their wild relatives. But should they really be eating grains and veggies every day?
Even though grains are unfashionable for humans and pets these days, there’s nothing wrong with them. Dogs and cats can digest grains, and they’re a fine ingredient in food as long as the nutrients are balanced. In other words, it’s fair to use an “if it fits your macros” approach, and grains often fit just fine.
There are two small caveats. One is that barley and soy tend to make dogs fart a lot. Another is that the more fiber a food contains—whether from grains, veggies, or the small amounts of fillers like carrageenan and guar gum—the more poop the dog is likely to produce. More expensive “premium” foods tend to result in less poop.
So, let’s say you find a grain-free food you like. That’s fine, but you’re paying extra for a food that’s nutritionally similar to the cheaper grain-containing foods. Grain-free foods may not have wheat or corn, but instead typically have pea flour, potatoes, and other starchy ingredients. As long as the food is nutritionally complete—and it will say so on the package—you should probably save your money.
What about the other reassuring-sounding words on the label? Most don’t mean what you think they mean. The definition of “natural” is so vague that it’s not very meaningful. There is no official definition of “holistic,” and even though “organic” has a specific meaning in human food, pet food laws have loopholes that let them call foods organic that don’t meet all the organic standards. “Human-grade” is another meaningless buzzword. Some pet foods and treats use it, but the AAFCO considers it misleading the way it’s typically used. Pet foods just aren’t the same thing that you would feed yourself, and that’s okay—your dog doesn’t mind.