Why?
Cabbage is a very fermentable cruciferous vegetable: gut bacteria break down its fiber and sugars, producing gas and sometimes bloating or soft stools. It also contains glucosinolates, compounds that can interfere with thyroid function when eaten raw in large amounts over time. Cat-specific data are limited, so the cautious approach is to cook it and keep portions tiny.
How much?
A teaspoon of well-cooked, plain, chopped cabbage, once in a while at most. No coleslaw, sauerkraut, stuffed cabbage or cabbage soup, which come with salt, mayo, cured meat or onion.
The risks
- Gas, bloating and belly pain
- Soft stools or diarrhea
- Possible thyroid effects from large amounts of raw cabbage
- Coleslaw and sauerkraut: mayo, salt, onion
Your cat ate some: what now?
A bit of cabbage is usually not serious. Watch your cat for 24 to 48 hours and call your vet if its belly is swollen and sore, it vomits repeatedly or has diarrhea that won't stop. If it was cabbage soup or a dish with onion, call your vet right away.
Better options
Cooked broccoli and cauliflower are slightly better tolerated, and green beans or zucchini are gentler still on the gut.
Common questions
Can cats eat kale?
Kale is in the same family and raises the same issues: gas, plus compounds that can affect the thyroid in large amounts. If you offer it, keep it to a tiny cooked portion, rarely.
Can cats eat coleslaw?
No. Coleslaw combines raw cabbage with a fatty mayo dressing and sometimes onion, so it's gassy, rich and risky. If you want to share, offer a small bite of plain cooked cabbage instead.
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.