Don't Fall Victim to the By-product Panic

You should be cheering, rather than sneering, at by-products

Published: August 07, 2017
Photo Courtesy Depositphotos

You've seen the commercials with a wide-eyed spokesperson in a pastel lab coat bleating, "Our organic pet cuisine features only four ingredients, none of them with more than two syllables in their all-natural, non-toxic names!" Camera pans left to show a shame-faced pet owner moaning, "Corn is the first ingredient. And chicken by-product is second. Woe is me for I have slain my loving furball with this grocery store pet swill!" Scene fades as sobbing and funeral dirge swell.

Before you run off to trash Buster's kibble, take a breath and get past the fear-mongering. Those commercials are marketing hype, not quality nutritional advice, and should be treated with the same skepticism (I hope) you give to political ads at election time. Let's talk about what some of those popular pet food terms really mean.

Meat by-product is the arch-villain in many pet food commercials. The sneer in the announcer's voice makes you imagine that by-products are the hair and feathers and manure-covered feet hosed off the slaughterhouse floor at the end of the day. Not true.

Remember the year that Buster snagged the leftover Thanksgiving turkey when you went to the kitchen for Tupperware containers, then raided the giblets out of the trash when you came in to investigate the noise in the dining room? And when you finally found him in the kitchen licking the bloody wrapper from the raw turkey, remember that look of utter joy on his sloppy Labrador muzzle? That was by-product bliss.

The Association of American Feed Control Officials defines meat by-products as "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 de-fatted low temperature fatty tissue, and stomachs and intestines freed of their contents. It does not include hair, horns, teeth and hoofs."

Many humans only want the muscle tissue and a little bit of fat for flavor. That leaves a lot of good food on each slaughtered carcass. The organ meats (kidney, liver, etc) are in fact more nutritious than the prime cuts of steak you want. Mince up all the by-products and mix them together and you have the basis of a nutritious pet food. You should be cheering, rather than sneering, at by-products.

Grains are the arch-villain's thuggish sidekicks. If you read the scary blog posts, grains are poor-quality fillers responsible for allergies, bad breath, and obesity. First, just because Buster is an omnivore and Peaches is a carnivore doesn't mean that they don't get value from plants. Meat and other animal tissues have essential amino acids and other nutrients not found in plants -- therefore, you can't make a cat vegetarian -- but grains like wheat and corn are highly digestible sources of carbohydrate and protein. Indeed, if you watch Peaches devour that chipmunk she caught in the yard, it's often the innards that go first, before any "meaty bits." And what's in chipmunk innards? Plant matter!

High-carbohydrate diets are often cited as a major contributor to the human obesity epidemic, so many pet owners find it logical to feed grain-free pet foods to keep their pets trim and healthy. But there are two big problems:

  1. Pets and people have different protein/carbohydrate requirements. The proportion of protein a healthy cat needs would increase the risk of cancer and metabolic diseases of a human.
  2. Grain-free is not the same as low-carb. Potatoes, apples, or peas are common substitutes for wheat and corn so you can actually end up with diets that are higher in carbohydrate.

As to allergies, "good" ingredients like beef, chicken, lamb, rice, or dairy are just as, or more, likely to cause hypersensitivity as "evil" ingredients like corn, wheat, or soy. It all depends on your pet's individual immune system.

"All-natural," "non-toxic" and "organic" are sexy terms that often don't have any real impact on nutritive value. AAFCO uses the USDA definition of organic, which forbids synthetic fertilizers, sewage sludge, irradiation, and genetic engineering in production. That sounds reassuring but doesn't necessarily mean organically produced food is safer or more nutritious than conventionally produced food. (The manure used in organic farming is still poop; the sun shining down on organic crops is also radiation.) One can argue that organic farming practices are better for the environment; if that's why you want to feed organic products, good for you.

I abhor the term "natural." It sounds all frilly and pretty and happy, but it's often useless for any practical purpose. AAFO defines natural as "derived solely from plant, animal or mined sources, either in its unprocessed state or having been subject to physical processing, heat processing, rendering, purification, extraction, hydrolysis, enzymolysis or fermentation, but not having been produced by or subject to a chemically synthetic process and not containing any additives or processing aids that are chemically synthetic except in amounts as might occur in good manufacturing practices."

And I'm not sniping at AAFCO. All the popular definitions of 'natural' are so broad as to be useless. There are many natural things that are disgusting or toxic (e.g., week-old road kill, saw dust, freshly mined arsenic, and bird poop) and many chemical things that can be quite beneficial in foods (e.g., certain vitamins, minerals, and preservatives).

Now that many people have gotten wise to "natural," restaurants and manufacturers have started using "clean" – an absolutely worthless term. What does that even mean? They refrained from throwing the food on the floor? They hose down the manufacturing line every day? They dunked the organic gluten-free chicken in Mr. Clean?

What should you be looking at when selecting a pet food?

  • Consider the form of food. Kibble, cans, and pouches all have their pros and cons. Choose the form(s) that you and your pet prefer.
  • Read the label. Ignore the pretty pictures and catchy slogans on the front of the bag. Turn it over and look at the ingredient list, the guaranteed analysis, and the AAFCO statement.
  • Ask your veterinarian if your pet has special nutritional requirements. An average, healthy adult dog or cat can do okay on most pet foods you find in the grocery store. Puppies/kittens, aging pets, and pets with health problems like kidney disease, diabetes, or food allergies may need special diets.
  • Go to the manufacturer’s website to find more information on manufacturing processes or ingredient sources. You may need to call them, but any reputable manufacturer will happy to talk to you.
  • Feed according to the label directions and see how they do on it for a couple of weeks. Happy and active and maintaining a healthy weight? Great! Not quite right? Adjust how much you're feeding or (gradually!) switch to a different food. Every pet's an individual so there can be a bit of trial and error involved in finding their "ideal" food.
  • Avoid the hype! WSAVA has some great tips on finding good quality information on dog and cat nutrition, as well as other recommendations for selecting pet foods.

So do me a favor. The next time you see one of those angsty pet food commercials, roll your eyes and change the channel because now you're too well-informed to fall prey to their nonsense jabbering.

Bonus fact: There's a lot of hype about having "real meat" as the first ingredient. Since ingredients are listed in weight order, it seems obvious that having chicken listed before corn is the sign of a better food. And I agree, I like the idea of most my dog's nutrition coming from animal sources. But wait a second. A lot of the weight in meat is from water/moisture. Grains have much less moisture content so pound-for-pound you get more energy from corn than chicken meat. Meat meal (which is ground animal tissue without all that water) is a concentrated source of protein. A pet food labelled "corn, chicken by-product meal" may actually be significantly more nutritious than a pet food labelled "chicken, corn."


Michele Beckett
December 3, 2017

I have raised dogs and cats on both foods and commercial.  Difference is 30 years and Toxic Chemicals allowed in farming.  Studies on humans prove carcinogens in Monsanto product esp roundup. Meat By Products are fine unless your animal has liver problem.  Also If my food source is in USA and inspected I am fine but so many foods are coming from Asia who does little inspection and food has been proven fatal to animals esp dogs   I would be a bit more committed to Organic.   But the label game is just that in all food so is it important to read, bet.   A healthy animal is going to live a better life than one whose owners cannot pay the expense of Vet Care.   Disease is not cheap. Home Made food is fine just make sure your Vet and you have Supplemental Program to get the proper Vitamins, Minerals, Fats, Protein. Always glad to read, but I never stop with one article or my pets would be dead by now.    I am on recall emails because it does matter  even organic foods have recalls. I asked Purina when the Proplan was not doing so well about their grains.  Purina honestly said they did not know what grains, what chemicals were used.  I stopped using ProPlan for years, cause if you do not know what you are buying then you do not know what you are feeding my dog.  That is unacceptable.

Janet, DVM
September 8, 2017

A Slaugh, the main difference in omega fatty acids I'm aware of is between grass-fed and grain-fed beef.  The fatty acid profile of grass-fed beef is much healthier.  Could this be what you're thinking of?  I am not aware of any reliable studies showing a difference in EFAs between foods labeled as "organic" and foods without that label.

A Slaugh
August 12, 2017

Overall, a great article!  However, I do take issue with your comment about organic food.  According to a meta-analysis published in the British Journal of Nutrition about 2 years ago, organic foods like meat and dairy do, in fact, contain significantly more Omega-3 fatty acids.  (I believe studies by the US Department of Agriculture also concluded there are different nutritional contents between organic and conventional, although I can't put my finger on them at the moment). Otherwise, I enjoyed this article very much.  Informative without being preachy. 

Lucia Lemmer
August 9, 2017

Thank you for the clear, concise and useful information.


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