What “By-Products” Really Mean in Pet Food

Few words in pet nutrition trigger more immediate panic than “by-products.”

You see it on a label and suddenly the internet voice starts:

“Fillers.”

“Waste.”

“Beaks and hooves.”

“Low quality.”

It sounds unpleasant. It sounds vague. And most of us don’t want to feed our pets something that feels like leftovers.

But here’s the truth:

The word “by-product” in pet food does not mean what most people think it means.

Let’s slow this down and unpack it clearly.

What Are By-Products in Pet Food?

By-products are parts of an animal that remain after the primary cuts of meat are removed for human consumption. These can include organs such as the liver, kidneys, lungs, and heart, as well as other parts like blood, bone, and sometimes the stomach or intestines.

Legally, the definition of by-products varies slightly depending on the country and regulatory body, but the Association of American Feed Control Officials (AAFCO) defines “meat by-products” as non-rendered, clean parts other than meat, including lungs, spleen, kidneys, brain, liver, blood, bone, and fatty tissue.

These parts are not inherently inferior; many are rich in nutrients essential for pets. For example, organ meats provide vitamins and minerals that muscle meat alone may lack.

Why Are By-Products Used in Pet Food?

By-products serve several important roles in pet food:

• Nutritional Value: Organs and other by-products contain essential nutrients such as vitamin A, B vitamins, iron, and amino acids. These nutrients support pet health, including immune function and energy metabolism.

  
  

• Sustainability: Using by-products reduces waste by utilizing parts of the animal that would otherwise be discarded. This approach supports more sustainable food production.

  
  

• Cost Efficiency: By-products are generally less expensive than prime cuts of meat, helping manufacturers keep pet food affordable without sacrificing nutrition.

  
  

• Texture and Palatability: Some by-products contribute to the texture and flavor that pets find appealing.

  
  

Common Misconceptions About By-Products

Many pet owners associate by-products with low quality or unsafe ingredients. This perception often comes from misinformation or misunderstanding of labeling terms.

• Misconception 1: By-products are “leftovers” or “garbage.”

By-products are not random waste. They are specific parts of the animal that can be highly nutritious. For example, liver is a by-product and is often considered a superfood for pets.

• Misconception 2: By-products are harmful or unsafe.

By-products used in pet food must meet safety standards set by regulatory agencies. They are inspected and processed to ensure they are safe for consumption.

• Misconception 3: By-products lower the quality of pet food.

Quality depends on the source and processing of ingredients, not just the label term. High-quality pet foods can include by-products as part of a balanced recipe.

Nutritional Value of By-Products

By-products can be a rich source of nutrients that muscle meat alone may not provide. Here are some examples:

• Liver: High in vitamin A, iron, and copper. Supports vision, blood health, and immune function.

• Kidneys: Provide B vitamins and essential fatty acids.

• Heart: Rich in taurine, an amino acid important for heart health, especially in cats.

• Lungs and Spleen: Contain proteins and minerals.

• Bone: Supplies calcium and phosphorus, important for bone health.

  
  

Veterinarians often recommend including organ meats in homemade pet diets for these reasons. Commercial pet foods that include by-products can offer similar benefits.

How Pet Food Labels Work

Understanding pet food labels helps clarify what you are feeding your pet. Here are some key points:

• Ingredient Lists: Ingredients are listed in order by weight before cooking. By-products will be named specifically, such as “chicken by-products” or “beef liver.”

  
  

• AAFCO Statements: Look for statements like “complete and balanced” which indicate the food meets nutritional standards.

  
  

• By-Product vs. Meal: “By-product meal” is a dried and ground form of by-products, often used in dry kibble. It is concentrated in nutrients.

  
  

• Meat vs. By-Products: Some pet foods list whole meat (like “chicken”) and by-products separately. Both can contribute valuable nutrients.

  
  

• Misleading Terms: Terms like “meat meal” or “animal digest” can sound vague. Research or ask manufacturers for clarification if unsure.

  
  
  
  

What to Consider When Choosing Pet Food with By-Products

• Source and Quality: Check if the pet food brand discloses the source of by-products. High-quality brands often source from inspected facilities.

  
  

• Balanced Nutrition: Ensure the food meets AAFCO standards for your pet’s life stage.

  
  

• Pet’s Health Needs: Some pets have specific dietary requirements or allergies. Consult your veterinarian if unsure.

  
  

• Transparency: Brands that provide clear ingredient information and manufacturing practices tend to be more trustworthy.

  
  

Final Thoughts

By-products in pet food are often misunderstood. They are not inherently bad or low-quality ingredients. Instead, they can provide important nutrients and support sustainable pet food production. Reading labels carefully and understanding what by-products mean can help pet owners make better choices.

If you feel uncertain about your pet’s diet, discussing options with a veterinarian can provide personalized guidance. Remember, the overall balance and quality of the diet matter more than any single ingredient term.

Feeding your pet well involves looking beyond labels and focusing on nutrition, safety, and your pet’s individual needs.