There are many reasons a cat might vomit, and different types of vomit including hairballs and bile (yellow liquid). This article is specifically about food vomit. Food vomit is when the cat throws up chunks of undigested food and typically occurs 20 minutes to 1 hour after eating.
When a cat vomits its food on a regular basis you can assume one of two things, either there is something medically wrong with the cat, or there is something wrong with the cat’s food.
Problems with Cat Food Linked to Causing Vomiting
A lot of cat foods uses cheap filler ingredients, and a lot of these ingredients are things cats cannot digest easily or have sensitivities to. While any ingredients can cause a reaction (particularly if it is something the cat is allergic to) corn and wheat are well known as problem causing ingredients for many cats. Cats are carnivores so normally they would not eat corn and wheat and as such many cats are sensitive to it and vomit as a result of it being hard to digest or because of sensitivities.
Another concern with the lower quality cat foods is that they use fat to add flavor. When a food uses a lot of filler (corn, by-products, etc.) the cat has to eat a lot more food to get its nutritional needs met, as such it also eats more fat. The fat can be hard on a cat’s stomach and may result in vomiting after eating.
In canned cat food you should note that “chunks in gravy” is usually harder on the cat’s stomach than pate. The gravy is carbohydrates and not beneficial to the cat anyhow.
Some pet foods use a lot of color dyes and these too can trigger vomiting in a cat that is sensitive to the dyes.
Cats can also have sensitivities to other ingredients, even things that most cats like (such as chicken), some cats who cannot tolerate certain meats tend to do fine on a lamb based cat food. Note that if a cat food contains “meat meal” where the meat source is not specified the meat could be anything.
Changing dry food brands or formulas too frequently can also result in vomiting. Although we tend to worry that our cats will get bored eating the same food day after day it is actually better for their stomach if they do. If your cat is on a good quality food, stay with it. If for some reason you change cat foods do so gradually.
Milk is not something cats should have, although most do like the taste of it. In some cats milk just causes stomach upset or diarrhea, but in others it can cause vomiting.
A food that is too rich for a cat’s stomach might also lead the cat to vomiting the food. An example of this might be senior cats fed kitten food.
The cat’s food could be old, rotten, or out of date.
Problems with the Cat Causing Food Vomit
A sick cat may vomit. If your cat is showing symptoms of being ill, such as lethargy, running a fever, weight loss, and so forth, you may want to consider that your cat is sick and needs veterinarian attention.
If your cat is having dental problems, or eating too fast, it might throw up its food.
In some cases a cat with intestinal parasites (worms) might vomit its food (and sometimes worms too).