The simple answer is that cats are attracted to tuna. They love the powerful smell and the robust flavor of this fish, and a spoonful of tuna has been known to make the medicine go down easily.

However, though not on the list of toxic foods for cats, tuna that's meant for people can cause health issues for cats. While a single bite may not do any harm, it's best to take tuna out of their bowl entirely.

A well-balanced meal plan for cats includes protein, essential fatty acids, vitamins, minerals, and other nutrients. When your kitty eats too little or too much of certain nutrients, health complications can arise.

Tuna on its own is not nutritionally balanced. For example, tuna has too much unsaturated fat and is not supplemented with Vitamin E or other antioxidants. Therefore, tuna should not be fed as your cat's primary source of nutrition.

If tuna is part of your cat's meal plan and you notice them acting out of sorts, consider taking them into your veterinarian for a wellness visit — it's always a good idea to get a baseline reading to ensure nothing serious is going on.

Cats can also be allergic to fish. The Merck Veterinary Manual lists fish as a top food allergen for cats, noting that common signs of an allergic reaction include itching, hair loss, red or swollen skin and red bumps. Cats with food allergies may also vomit and experience diarrhea, gas and a loss of appetite if they encounter an ingredient they're sensitive to. If you notice any of these symptoms, call your veterinarian right away to determine the causes and create a treatment plan.

Tuna is high in mercury, a toxic metal. Frequent consumption of tuna may also lead to mercury poisoning explains Cailin Heinze, a veterinary nutritionist at the Cummings School of Veterinary Medicine at Tufts University. Symptoms of mercury poisoning include dizziness and loss of coordination and balance. Pet parents should keep albacore tuna, in particular, away from cats because it "is from a larger species of tuna with mercury levels almost three times higher (than chunk-light)," says Heinze.

So, can cats eat tuna? Tuna is not nutritionally balanced and should not be fed as a large part of your cat's meal plan. Even giving canned tuna as a treat can lead to health issues, especially if it is given in large amounts or frequently. To ensure your feline friend is getting the balanced nutrition they need without extra calories or toxic metals, choose a healthy cat food that uses tuna in a way that still meets their nutritional needs and satisfies their taste buds. Visit a Veterinarian for more information regarding what nutrition is adequate for your pet.