Walk into any pet store. Look at the boutique kibble wall. Find a bag with a green leaf icon or a “natural” callout. Read the back. You will not see by-product meal listed. The brands that charge $90 for a 24-pound bag built their entire positioning around the idea that by-product meal is filler, that responsible pet parents avoid it, and that the cheap mass-market brands are full of it.
The reality is more boring and more interesting. Let’s go through it.
What AAFCO actually defines
From the AAFCO Official Publication: “Chicken by-product meal consists of the 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 unavoidably in good processing practice.“
So: chicken organs and frame parts. Not feathers, not beaks, not hooves (chickens don’t have hooves), not road kill, not euthanized shelter pets. Just the parts of the chicken that don’t go into nuggets at the human plant down the road.
Beef by-product meal, lamb by-product meal, salmon by-product meal, same idea, different species. The “by-product” classification just means “not the part the human food industry wanted.” It’s a regulatory and economic category, not a quality category.
Why organ meat is actually good
Liver is the most nutrient-dense organ in the body. It contains roughly five times the iron of muscle meat, ten times the vitamin A, and significantly more B vitamins, copper, and zinc. Heart is essentially red muscle and contains taurine, which is critical for cats and useful for dogs. Kidneys contain selenium and B12 in concentrations you don’t get from steak.
| Nutrient | Where it’s most concentrated |
|---|---|
| Iron | Liver, heart, kidney |
| Vitamin A | Liver |
| Vitamin B12 | Liver, kidney, heart |
| Folate | Liver |
| Selenium | Kidney, liver |
| Copper | Liver |
| Taurine | Heart |
| Zinc | Liver, organs generally |
A dog eating only chicken breast meat would be missing nutrients that a dog eating chicken breast plus chicken liver and chicken heart would not. Whole-prey-modeled raw diets, which are about as far from kibble as you can get on the marketing spectrum, deliberately include 5 to 10% organ meat for exactly this reason.
Wild canids that catch a deer eat the organs first. They eat them while they are still warm. They prefer them. The “muscle meat is better than organ meat” intuition is a human cultural preference, not a nutritional ranking.
So why does by-product meal have a bad reputation?
Two reasons.
One: the term itself sounds gross
“By-product” suggests waste, leftover, lesser. In English, it’s a degrading word. In other languages, organ meat has its own positive vocabulary (offal, abats, frattaglie) and consumers don’t have the same aversion. American grocery stores sell roughly 1% as much liver and kidney as European ones do, per capita. Pet food marketers in the US correctly identified that “by-product meal” was a term they could use against competitors who used it.
Two: the unnamed-source version is genuinely worse
“Meat by-product meal” or “poultry by-product meal” without a species named is the version that deserves caution. The species can change batch to batch, the source can be variable, and the quality is harder to track. When critics attack by-product meal, they usually have unnamed by-products in mind. They don’t always make the distinction clear.
The brands that use named by-products on purpose
Hill’s Science Diet, Royal Canin, Purina Pro Plan, and Iams all use named by-products (chicken by-product meal, mostly) in many of their recipes and don’t apologize for it. These companies employ board-certified veterinary nutritionists. They run feeding trials, which is a high bar that almost no other brand clears. They use named by-products because the nutritional case for them is solid.
The reason their bags don’t get marketed as “no by-products” is that they don’t want to validate the framing. If you market against a thing, you’re conceding that the thing matters. These brands sell the recipe, not the absence of an ingredient.
If your dog is doing well on a recipe with named by-product meal, the recipe is doing its job. The marketing on the boutique bag doesn’t change that.
Why the boutique brands took the opposite position
This is the part that gets glossed over in most ingredient discussions. The “no by-products” positioning was a strategic choice by smaller brands trying to differentiate against the major players. If you can’t compete with Hill’s on feeding trials (because trials cost six figures per recipe and you’re a small brand), you compete on something else. “We don’t use by-products” was that something else.
The marketing worked. By 2010, “no by-products” was a default expectation in the premium and ultra-premium segments. The brands that built their identities around it could charge $30 to $50 more per 30-pound bag than the brands using named by-product meals. The price premium was the entire point.
None of this means the boutique brands make bad food. They mostly don’t. It means the “no by-products” claim is a marketing position, not a quality signal.
How to read a by-product line on a label
Two questions, both answerable in five seconds:
- Is the species named? “Chicken by-product meal” yes. “Poultry by-product meal” no. “Meat by-product meal” no.
- Is the brand a feeding-trial brand? If yes, the named by-product is almost certainly fine. If no, the named by-product is probably still fine but the brand hasn’t validated the recipe end-to-end.
For the long version of how to read the rest of the label, see the label reading guide. For the difference between meat and meat meal, see meat meal vs fresh meat.
The European frame
European pet food labels use the same general structure as US labels but the consumer culture around organ meat is different. In France, Italy, and Germany, you can find pet food that explicitly markets the inclusion of liver, kidney, and other organs as a feature. The bags say things like “with 8% chicken liver” or “rich in offal” (in the local language). American pet food marketing would not use this approach because the words don’t translate to a positive consumer reaction.
The food itself is similar. The marketing isn’t.
Common questions
Is by-product meal bad for dogs?
No, when it’s named. Chicken by-product meal, lamb by-product meal, and other named-species by-product meals are nutritionally valid and used by feeding-trial brands routinely. Unnamed ‘meat by-product meal’ or ‘poultry by-product meal’ is the version actually worth avoiding because the species can change batch to batch.
What’s actually in chicken by-product meal?
By AAFCO definition, chicken by-product meal is the rendered, ground product made from clean parts of the chicken carcass, including necks, feet, undeveloped eggs, and internal organs (liver, heart, kidney, spleen). It excludes feathers, beaks, and most state regulations exclude the digestive tract contents. It does not include road kill or euthanized shelter pets.
Why do vets recommend dog foods that contain by-products?
Because the nutritional case is solid. Organs are more nutrient-dense than muscle meat, and named by-product meals provide a good amino acid and micronutrient profile at a lower cost than fresh muscle meat. Vets who recommend Hill’s, Royal Canin, and Purina Pro Plan are recommending recipes that frequently include named by-product meals.
Is ‘meat by-product meal’ the same as ‘chicken by-product meal’?
No. ‘Meat by-product meal’ without a species named is the version to be cautious about because the source animal can vary. ‘Chicken by-product meal’ is a named, specific ingredient. Always look for the species name.
Are by-products in dog food the same as the by-products in human food?
Conceptually yes. The ‘by-products’ the pet food industry uses are the same parts of the animal that get sold to the human food industry as offal in cultures where organ meat is more popular. It’s the same liver, the same heart, the same kidney. The labeling and the marketing are different in pet food.
Why do some boutique dog food brands market ‘no by-products’?
Because it’s a marketing differentiator that lets them charge a premium. The claim resonates with American consumers who associate ‘by-product’ with ‘waste,’ even though the underlying ingredient is nutritionally valid. The brands that took this position in the 2000s built premium identities around it. The major vet-recommended brands declined to play along and continue using named by-products in their recipes.