Sodium Metabisulfite in Pet Food

Grade D-4 ptsPreservatives

What It Is

"A synthetic sulfite preservative and antioxidant."

Health Impact

Sulfite preservatives like this one are known to destroy thiamine (vitamin B1) in the food they're added to — a genuine nutritional cost, not just a safety question — and they're also recognized human allergens capable of triggering asthma-like reactions in sensitive individuals. Safer, non-thiamine-destroying preservatives exist and are widely used instead. Score: 2/10.

Why This Grade

A meaningful red flag: an unnamed source, heavy processing into a by-product or digest form, or documented regulatory scrutiny in at least one country. -4 pts deducted.

Sources & Further Reading

Frequently Asked Questions

Is Sodium Metabisulfite safe for dogs and cats?

Rated D (-4 pts) by PetPro-tectors™. Sulfite preservatives like this one are known to destroy thiamine (vitamin B1) in the food they're added to — a genuine nutritional cost, not just a safety question — and they're also recognized human allergens capable of triggering asthma-like reactions in sensitive individuals. Safer, non-thiamine-destroying preservatives exist and are widely used instead. Score: 2/10.

What is Sodium Metabisulfite in pet food?

A synthetic sulfite preservative and antioxidant.

Related Preservatives Ingredients

Mixed Tocopherols (Vitamin E)Rosemary ExtractGreen Tea ExtractCitric Acid
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Sources: FDA, AAFCO Official Publication, National Toxicology Program,
WSAVA Global Nutrition Guidelines, Journal of Animal Science.

PetPro-tection League™