Red 3
Last updated: February 11, 2026
Table of Contents
Quick Summary
Red 3 Red 3 (Erythrosine) is a synthetic cherry-red dye derived from petroleum, used to create red color in pet food and treats.
What It Is
Red 3 (Erythrosine) is a synthetic cherry-red dye derived from petroleum, used to create red color in pet food and treats.
Compare to Similar Ingredients
- vs. beet juice color: Red 3 (erythrosine) is a synthetic petroleum-based dye (FD&C Red #3) linked to cancer and banned in cosmetics, while beet juice color is a natural red colorant from beets—beet juice is far safer.
- vs. red 40: Red 3 is a synthetic petroleum-based dye with cancer concerns, while carmine is a natural red dye from crushed cochineal insects—both add only color, but carmine is safer (though not vegan).
Why It's Used in Dog Products
Manufacturers include red 3 in dog food, treats, and supplements for several reasons:
- Creates bright red color to appeal to humans
- Makes food look more "meaty" or appealing
- Provides color consistency across batches
- Masks ingredient variations
- No nutritional or functional benefit for dogs
Quality Considerations
When evaluating red 3 in dog products, it's important to understand protein density, amino acid profile, digestibility, and sourcing quality. This ingredient's quality and appropriateness can vary significantly based on sourcing, processing, and the specific formula it's used in.
Red 3 provides zero nutritional value and serves only cosmetic purposes for human perception. Dogs are not influenced by food color. Red 3 is the most controversial synthetic dye—it was banned in cosmetics in 1990 due to cancer concerns from animal studies showing thyroid tumors. However, it remains FDA-approved for food use. Several studies link it to behavioral changes and thyroid dysfunction. There is absolutely no legitimate reason to include Red 3 in dog food.
Potential Concerns
While red 3 can be appropriate in dog nutrition, pet owners should be aware of allergies, protein digestibility, and quality variations between named and generic sources. Individual dogs may respond differently to the same ingredient based on their health status, age, and sensitivities.
Red 3 is one of the worst ingredients you can find in dog food. Banned in cosmetics for cancer concerns but still allowed in food—that alone should raise red flags. Synthetic dyes serve zero purpose for dogs and exist only to fool human buyers. Red 3 specifically has concerning research on thyroid effects and behavioral changes. Any food containing Red 3 or other FD&C dyes signals a manufacturer prioritizing marketing over health. Avoid entirely and choose brands with no artificial colors or natural colorants like beet juice.
Frequently Asked Questions
Is red 3 safe for dogs?
Yes, red 3 is safe for dogs when used appropriately in properly formulated dog food. As with any ingredient, individual dogs may have sensitivities, so monitor for any adverse reactions when first introducing products containing this ingredient.
What does red 3 do in dog products?
Red 3 (Erythrosine) is a synthetic cherry-red dye derived from petroleum, used to create red color in pet food and treats. Dog food manufacturers include this ingredient to provide creates bright red color to appeal to humans and provide makes food look more "meaty" or appealing.
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