Ingredients to Watch Out For

Not All Ingredients Are Equal

While commercial cat foods must meet safety standards, the quality of ingredients varies enormously between products. Learning to identify less desirable ingredients helps you make better choices — but it also requires understanding the nuance behind common claims. Not everything marketed as "bad" is truly harmful, and not everything marketed as "premium" is genuinely better.

Ingredients Worth Questioning

Meat By-Products

• What it is: Organs, blood, bone, and other parts — essentially everything except skeletal muscle meat
• The nuance: By-products aren't inherently bad. Cats in the wild eat organs enthusiastically, and liver, heart, and kidney are nutrient-dense. The concern is quality consistency — "meat by-products" without species identification could include widely varying ingredients.
• Better option: Named by-products (e.g., "chicken liver," "turkey giblets") are transparent and often nutritious

Corn, Wheat, and Soy

• Used primarily as cheap fillers and protein boosters in budget formulations
• Plant protein is less bioavailable to cats than animal protein — a cat extracts fewer usable amino acids per gram
• Some cats develop food sensitivities to these ingredients, manifesting as skin issues or digestive upset
• Small amounts aren't harmful, but these shouldn't dominate the ingredient list

Artificial Colors and Flavors

• Cats don't see food color the way we do — dyes like Red 40 and Yellow 5 are purely for human marketing appeal
• Artificial flavors may mask the taste of low-quality base ingredients
• Look for foods colored naturally by their actual ingredients

Carrageenan

• A seaweed-derived thickener used in many wet foods to create a consistent texture
• Some studies suggest it may cause gastrointestinal inflammation in sensitive animals
• Many premium brands have reformulated to remove it
• Not a dealbreaker, but worth noting if your cat has GI sensitivities

Red Flags

These ingredients should raise more serious concerns:

• "Meat" or "animal" without naming the species — could be rendered from any source, with inconsistent quality and nutrition
• Sugar or sweeteners — no nutritional purpose whatsoever for cats; used to increase palatability in lower-quality foods
• Excessive salt — used to make bland ingredients taste acceptable
• BHA, BHT, ethoxyquin — artificial preservatives with debated safety profiles; look for foods preserved with mixed tocopherols (vitamin E) or rosemary extract instead

The 5-Second Label Check

When you're standing in the pet food aisle, use this quick filter:

1. First ingredient: Is it a named animal protein? (Good: "chicken." Bad: "poultry by-product meal.")
2. First five ingredients: Are at least 3 of them animal-based?
3. Artificial preservatives or colors: Are BHA/BHT/dyes listed? Skip it.
4. AAFCO statement: Does it say "complete and balanced"?

If a food passes all four checks, it's worth a closer look at the guaranteed analysis.

The Bottom Line

Focus on foods with named animal proteins as the primary ingredients, minimal fillers, and natural preservatives. No single ingredient is an automatic dealbreaker, but the overall ingredient profile tells the story of food quality.

Sources

• Tobacman, J.K. "Review of harmful gastrointestinal effects of carrageenan in animal experiments." Environmental Health Perspectives, 109(10), 2001. View source
• Roudebush, P. et al. "Ingredients and foods associated with adverse reactions in dogs and cats." Veterinary Dermatology, 11(3), 2000. View source
• AAFCO. Official Publication. Association of American Feed Control Officials, 2024. View source