Some cat's owners still don't know that some human foods are very dangerous for cats. And I think that information about what cats can eat or not is very useful for their owners, so let see a list of human foods that toxic to cats now.
Onions, Garlic, & Related Root Vegetables
Onions contain a substance (N-propyl disulphide) which destroys red blood cells in the cat, causing a form of anemia called Heinz body anemia. Garlic contains a similar substance in a lesser amount.
Tomatoes, Green (raw Potatoes)
These foods are members of the Solanaceae family of plants, which includes the Deadly Nightshade, and contain a bitter, poisonous alkaloid called Glycoalkaloid Solanine, which can cause violent lower gastrointestinal symptoms. The Feline Future web site offers a rare description of a cat which was close to death from ingesting just one cherry tomato.
It's becoming more widely known that chocolate is very toxic to both cats and dogs. Theobromine is the offending substance here. Janet Tobiassen Crosby, D.V.M. has an excellent article on the symptoms, effects, and treatment of chocolate toxicity.
Grapes and Raisins
These foods' toxicity has mainly been found in dogs, in quantities of varying amounts. The ASPCA advises: "As there are still many unknowns with the toxic potential of grapes and raisins, the
Although milk is not toxic to cats, it may have adverse effects. Simply put, adult cats fed a nutritious diet don't need milk, and many cats are lactose-intolerant, which means that the lactose in milk and milk products produces stomach upset, cramps, and gassiness.
If your cat loves milk, and begs for it, a small amount of cream may be okay, two or three times a week. (The more fat in the milk, the less lactose.) Another compromise is CatSip, a product made from skim milk with an enzyme added that helps the digestion of lactose. Catsip is available in supermarkets such as Safeway, Albertson's and A&P, as well as pet products chains, such as PetSmart and Petco.