Cats can eat cabbage. Cabbage contains trace elements that can supplement a cat's nutritional needs, thus improving its immunity. Owners can feed their cats cabbage in moderation, but not in large quantities, and it should not be their cat's main food. Overfeeding may cause indigestion, and making cabbage a primary food source can lead to malnutrition. 
What cats cannot eat
1. Dried fish: Sun-dried fish contains a relatively high amount of magnesium, which can easily induce and cause urinary tract stones or urinary system diseases in cats, so try to limit their intake. An adult cat needs about 0.3 to 0.5 grams of salt per day, so be careful not to add too much salt to their food.
2. Human food: Our food contains a lot of oil, salt, and other seasonings, some even containing spices, which are unsuitable for pets. An adult cat or dog only needs food with a salt content of 50%. Too much oil and salt are bad for their health. Spicy food is even worse; meats with spices can dull a cat's sense of smell and cause gastrointestinal discomfort. For example, while cats may like to eat KFC chicken, it should not be given to them.
