Cats can have imitation crab, but it should only be given in very small amounts and very occasionally as a treat. Imitation crab is made from fish paste called surimi, which is not toxic to cats but is highly processed and contains several ingredients such as added salt, starch, sugar, and preservatives that are not healthy for cats. Regular or large amounts could lead to health issues like dehydration, weight gain, high blood sugar, kidney problems due to high phosphorus, and other digestive issues. Additionally, imitation crab is nutritionally inferior to real crab meat, lacking essential proteins and nutrients that cats need. Therefore, imitation crab is not recommended as a regular part of a cat’s diet. It's best to avoid crab shells or legs as they can be a choking hazard and cause internal damage.