Cats need to eat a well-rounded diet that includes proteins, fats, carbohydrates, vitamins and minerals, so you may assume that they can eat many of the same foods that people do. However, there are many foods in your kitchen that aren't ideal for your feline friend. Here are four foods that you shouldn't feed your cat.

Milk

While kittens may like to lap at a bowl of warm milk, milk isn't a necessary part of a cat's diet after they've been weaned. Once your cat has been weaned, they start to lose their ability to break down lactose, which is the sugar in milk, and this can leave them lactose intolerant. When cats are lactose intolerant, they can get a sick stomach or even severe diarrhea after they drink milk. If you must give your cat milk, give them lactose-free milk.

Raw Meat

Since your cat will kill and eat birds, toads, mice and other wild animals in your backyard, you may not think anything of giving them some raw beef or chicken from your fridge. However, this meat can pick up a lot of bacteria during slaughtering, processing or transport. A Consumer Reports study tested samples of ground beef from stores around the United States and found that every sample was contaminated with fecal bacteria. If you want to feed your cat meat, make sure to cook it properly and follow the same food safety procedures that you'd use if you were feeding a human family member.

Tuna

Cats love to eat tuna, but human-grade canned tuna should be avoided. Tuna has a lot of unsaturated fat, and if your cat eats too much of this fat, they could become deficient in Vitamin E. Becoming deficient in this vitamin makes your cat's fatty tissue inflamed; this can be a very painful condition. Instead, feed your cat a canned cat food that contains tuna. Since these foods contain other ingredients, not just tuna, they're better for your pet. 

Onions

It's common knowledge that dogs can't eat onions, but you may not know that the same is true for cats. Thiosulphate, an ingredient in onions, is toxic to both types of pets. If your cat eats small amounts of onions over time—which can easily happen if they like to beg for table scraps—they could become poisoned. If you like to feed your cat table scraps, make sure to not give them anything that contains onions.

To keep your cat healthy, avoid feeding them these four foods. For more information, contact your cat's vet (like those at Stewartstown Vet Services).