Kale

Kale is a leafy vegetable in the cabbage family, used dried and in small amounts in a few cat foods. It contains vitamin K and fiber. We found no FDA or Merck guidance on kale in cat food specifically, and cat studies are lacking. If your cat has a thyroid condition or urinary stones, ask your veterinarian about leafy green ingredients.

Kale is added as a leafy green with vitamin K and fiber, and as a familiar whole-food name. The Merck Veterinary Manual notes that a cat's gut bacteria usually produce enough vitamin K, so kale is not needed for that vitamin in a complete diet. The amount in dry cat food is small.

Source: merckvetmanual.com

There is no evidence that the small amount of kale in commercial cat food causes anemia. Some brassica plants contain sulfur compounds that have caused blood problems in grazing livestock eating large amounts, but that is a different situation from a dry cat food with a small amount of greens. Signs such as pale gums need a veterinary exam.

Cats need vitamin K for normal blood clotting. The Merck Veterinary Manual says gut bacteria typically supply enough, though antibiotic treatment that disturbs gut bacteria can lead to deficiency. Many cat foods also add vitamin K in a synthetic form. Kale contains vitamin K, but the small amount in kibble is not a cat's main source.

Source: merckvetmanual.com

Pettings gives kale 3 out of 5 and lists it as a fruit or vegetable ingredient. It appears on 3 of the 149 dry cat foods we list. The page groups kale with other leafy greens such as collards, all used in small amounts. Each food's page shows how it scores overall.