Common Foods That Are Harmful To Cats

Many owners like to enrich their cat's diet with the occasional treat, often a piece of food prepared for the human residents of the house. However, there are common foods that are harmful to cats and it's up to owners to know what they are and avoid them whenever possible.

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Seemingly innocuous treats could pose a major threat to your cat's health and well-being. With some, a very small amount may be tolerated but a larger dose or regular consumption can be harmful. Others are toxic enough to cause severe symptoms if ingested, even in small amounts.

You should never give any of the foods in this list to your cat -

  • Onions and garlic contain compounds that can break down a cat's red blood cells.
  • Alcohol is very toxic for cats. It only takes a few spoonfuls to kill a cat.
  • Coffee, tea and chocolate are dangerous to cats. Caffeine, as well as some ingredients found in chocolate, are toxic to cats even in small amounts.
  • Xylitol is a common sweetener contained in gum, candy and toothpaste. It can cause liver failure in cats.
  • Yeast dough could ferment and expand after ingestion, causing severe stomach pain. What's more, the yeast produces a certain amount of alcohol which in itself is toxic to cats.
  • Grapes and raisins don't seem to adversely affect cats but they are known to be harmful to dogs, and without established contradicting evidence pertaining to cats, you should avoid feeding them to your cat in any amount.
  • Avocados attract some cats due to their high-fat content. However, it can be harmful to cats and upset their stomach.
  • Nuts in general and Macadamia nuts specifically may pose a health risk for cats. While there is no concrete evidence for this, it's best to avoid them altogether.
  • Almonds and other fruit kernels are also toxic to cats due to their high content of cyanide.
  • Potatoes and tomatoes both contain toxic compounds which are dangerous to cats, especially when they are still green. Ripe tomatoes should be safe, as are any cooked tomatoes or potatoes.

The foods in the above list are usually not very attractive to cats. Unless you feed your cat leftovers of human meals, they are unlikely to come across nuts, tomatoes, onions or avocados in their menu.

However, there are common foods that are harmful to cats which may seem like "classic" ingredients of cat food. The following list contains several items which seem innocuous enough but can be dangerous when ingested in large quantities. What's more, they are indeed appealing to cats, so the risk of increased consumption is higher -

  • Tuna prevents absorption of certain nutrients. Do not offer tuna to your cat very often. Most cats love the taste of tuna, and cats have been known to be spoiled by owners to the point of eating nothing but tuna. Feeding exclusively on tuna will cause a cat to develop a painful disease called Steatitis, or "Yellow Fat Disease".
  • Raw eggs and raw fish can prevent the absorption of certain forms of vitamin B. Feed in moderation, if at all. Depending on the source and preparation, any raw food also poses some risk of bacterial contamination. Read more: Can I Feed My Cat A Fish Based Or Fish Flavored Diet Salmonella In Cats - 9 Things Every Cat Owner Needs To Know
  • Liver contains high levels of vitamin A. The cat's body cannot get rid of excess vitamin A and in high doses, this can be toxic and even fatal.
  • Dairy products can cause diarrhea and an upset stomach. Most cats, especially adult cats, are lactose intolerant. You can feed yogurt and kefir in small quantities as they have reduced levels of lactose.

In addition, use common sense and avoid giving your cat treats that contain too much fat and salt. If your cat is overweight, underweight, or if she is a senior cat or suffers from a chronic illness, it's best to consult your vet regarding both their overall nutrition and what treats should be given.

How to Prevent Ingestion of common foods that are harmful to cats

Fortunately, some of these foods are not appealing to cats, at least not in their natural form. With most cats, you don't have to worry about them binging on candy or chocolate, sipping your tea, or biting into raw onions. There are exceptions to this rule though, so watch your cat carefully and if you know them to be attracted to any of these foods, take extra care to keep it out of reach.

With all cats, be on the alert for the consumption of stuff they do like, be it tuna, dairy products or alluring, yet dangerous, combos such as coffee and cream.

Avoid trouble by following these rules - 1. Do not offer any of the foods mentioned here as treats. 2. Store these foods in a safe place, inside closed containers and out of the cat's reach. 3. Before serving any "human food" to your cat, stop carefully read labels and consider the ingredients. 4. Even with safe foods, always serve them fresh and unspoiled. Check for signs of mold and never serve anything that's past its expiry date. 5. Don't leave wet food out for too long without refrigeration.

Avoiding common foods that are harmful to cats will keep your cat healthier both in the short and long run. It is worth the effort!

Read more: Is Your Cat Addicted To Treats?

Comments? Leave them using the form below. Questions about your cat? Post them in the cat forums.

The forums are the only place where you can get quick answers to your cat-related questions. Please do not use the comments section to ask questions about your cat.

18 comments on “Common Foods That Are Harmful To Cats

tarasgirl06 February 4, 2019
Thanking you for yet another informative, educational, excellent article. And also thanking you for pointing out that the animal products referenced refer to non-cat-food sources. Tuna CAT FOOD is okay, though I am thinking it shouldn't be exclusive. Liver IN cat food is okay, as long as it is part of a balanced diet of high quality cat foods. Egg IN cat food is okay, as long as it is an ingredient, not an exclusive diet. And unlike quite a few people, I would not feed raw foods, period.
love4animals August 12, 2016
Do not buy Kit N Kaboodle because it blocks their kidneys so they can not urinate. I had to put 3 of my children(cats) to sleep because of this food. If anybody is interested I have a link to click on to read all about this killer cat food.
mattkat June 27, 2016
Okay, thanks. We hardly give it to them anyway.
Anne June 27, 2016
@MattKat As mentioned in the article, it's macadamia nuts that are the main suspect and even then there's not a whole lot of concrete evidence. The recommendation is to err on the side of caution and avoid nuts as they are not something cats need to eat anyway. I don't know of information suggesting that peanut butter is toxic to cats but it does contain a lot of fat and could cause upset stomach in large quantities. Licking a little bit peanut butter once in awhile should be ok.
Anne June 27, 2016
@JMJimmy liver is great as long as it's in moderation and as part of an overall balanced diet. Also, processing the liver by cooking helps. The problem is with owners who feed raw liver as a treat almost exclusively because they see how much their cat loves it. It has high fat content which appeals to cats so they can become addicted to raw liver.
mattkat June 26, 2016
Thanks! I will print this out. It says to not give cats nuts, but does that count peanut butter?
JMJimmy June 19, 2016
Interesting, I find it strange that one of the primary ingredients in many wet foods seems to be liver...
kawaiikoneko August 11, 2015
Wow! Tuna?!? Had no idea well no more tuna for Bentley! Also Dairy products so I guess I won't be feeding my cat milk either.
    Puss in boots February 18, 2021
    Hi I believe it’s the lactose in milk that cats can’t tolerate in my experience lactose free milk can be a treat for you puss
kitty momsy April 24, 2014
Very informative and interesting article.  I have been feeding my kitties regularly with tuna. I never thought it's bad for them. =(   @Ann ~ Thank you also for the link you provided Nutirion Forum.  I will definitel be check it out.
StefanZ August 31, 2013
Liver in normal doses is ok and even good. It is excessive use which is dangerous, may poison by excess of vitamine A. Supportive structures tends also to be in-boned. But normal, now and then, just a small part of the food, is OK.
StefanZ August 31, 2013
Its the raw white of eggs which isnt good. Cooked eggs white is ok, very much proteins. Raw egg yolk (the yellow) is EXCELLENT and mild nourishment! Really first grade. Cooked yolk is probably still good nourishment, but the enthusiastic receipts talk about raw. Observe, in some countries its common with salomonella in eggs. That is why in these countries eggs should be well cooked / boiled. Or at very least, thoroughly rinsed off with boiling hot water and soap, and be careful so the yolk doesnt touch the shell. This way the risk is much lesser (although not null).
simplysejaxo April 18, 2013
I occasionally feed my kitten tuna; apart from that he eats dry food ?
Anne February 7, 2013
@bellesmama - the risks mentioned in the articles are not attributed to any kind of commercial cat food, canned or dry. The problem is only with feeding actual egg, fish and tuna. For recommendations about cat food, please do visit our Nutrition forum!
bellesmama February 7, 2013
So what would you suggest for a dry cat food that doesn't have raw fish, egg and tuna flavors? I am asking for a friend, after reading this article, I told her about it and that's the kinds of dry food she feeds her cats.
xahm3d February 4, 2013
thank you for the information! i was feeding my cat only tuna for a week :O
lossy January 30, 2013
i found this very interesting, who would have thought that Tuna would be harmful to cats. Glad i read this, as i'm trying to switch my cat from a dry food diet to a wet food diet. It would have been very easy to feed him Tuna. Thanks for this article!
sweetlilly January 20, 2013
Very informative & interesting article!!!

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