Why?
Cooked potato isn't toxic to cats, but it gives a carnivore almost nothing. The trouble is the recipe: milk contains lactose cats digest poorly, butter and cream are very fatty, and salt isn't good for them. Instant or store-bought mashed potatoes often contain salt and sometimes onion, garlic or nutmeg.
How much?
At most a teaspoon of potato boiled and mashed with nothing added, once in a while. Keep it an exception, not a side dish.
The risks
- Diarrhea from the milk and butter
- Vomiting if it's very rich
- Weight gain if given often
- Anemia if it contains garlic or onion
Your cat ate some: what now?
A small amount of regular mashed potatoes usually isn't serious: watch for diarrhea or vomiting for 24 to 48 hours. Call your vet if symptoms appear or last, if your cat ate a lot, or if the mash contained garlic or onion.
Better options
A teaspoon of plain cooked pumpkin brings fiber that helps digestion. For a real treat, plain cooked chicken is hard to beat.
Common questions
Can cats eat garlic mashed potatoes?
No. Garlic is toxic to cats even when cooked and mixed into a dish. If your cat ate some, call your vet, especially if it was more than a lick.
Can cats eat instant mashed potatoes?
It's best not to. Instant mixes often contain salt, milk powder and sometimes onion or garlic flavoring, so check the label and skip it when in doubt.
This information is general and does not replace advice from a veterinarian. If your cat has swallowed something toxic, call your vet or an animal poison control center right away, without waiting for symptoms.