Can Cats Eat Mayonnaise

It is safe for cats to eat a little mayonnaise, but an excessive amount will be bad for their health and may even be toxic. There isn’t any reason for you to feed your cat any amount of homemade or store-bought mayo and it could be harmful for their health.

Lemon juice is a common ingredient in mayonnaise and it is toxic to cats, even in small quantities. Some recipes for mayo use vinegar to add flavour instead of lemon juice. While this makes vinegar safer for your cat to eat, the ingredients and their nutritional values do not line up with the diet of a healthy cat.  

Is it safe for cats to eat mayonnaise

If your cat only ate a small amount of mayonnaise, perhaps a quick lick or a spoonful, they will probably be fine. The most immediately dangerous ingredient in plain mayo is lemon juice. Lemons are toxic to cats, but it will take a lot of mayo for your cat to suffer from the effects of this. By the time your cat eats this much mayo, they will probably also be suffering from eating too much oil in one go.

Cats might eat mayo because they like the fats in it. If you have caught your cat eating a large amount of mayo keep an eye on them for the next couple of days and pay special attention for the immediate following hours. It’s quite likely that your cat will feel uncomfortable and vomit or have diarrhea. If you are uncertain about your cat’s health you should take them to a vet immediately. Its most likely that they will be uncomfortable and you may be recommended to give them a bland diet for the next week or so.

Lemon poisoning in cats will cause some discomfort, but assuming you take them to a vet for a treatment they should quickly recover. You will know if your home-made mayo has lemon and how much lemon it has. Store-bought mayo normally uses vinegar instead of lemon as it is cheaper, but you can check by looking at the ingredients list on the packaging or online.

If your cat is somehow regularly eating mayo, their general health is at risk. Mayo is primarily made of unsaturated fats. Cats need some fat in a healthy diet, but they will be getting this through their usual cat food. Anything else is excess fat and can cause them to quickly gain weight, especially if they are an inactive indoor cat.

You need to be much more concerned if your cat ate mayonnaise containing flavourings in it. The flavour to look out for in particular is garlic mayo.  

Can cats eat aioli or garlic mayo?

Aioli or garlic mayo may pose a bit more of a health risk to your cat. This can be a problem as it’s normal for use it as a dip for foods, like cooked meat, that cats will naturally be drawn to.

The problem is the garlic inside of the sauce. Garlic is part of the allium family, these foods can be poisonous for cats that eat a lot of garlic. This can either happen all at once or over a long period of time with a gradual intake.

It takes one gram of garlic per five pounds of cat to be toxic. The average cat weighs about ten pounds so it only takes two grams, or about half a clove of raw garlic, for your cat to suffer. Its easy for small portions of aioli or garlic mayo to have this much raw garlic so you should always be careful with your food around your cats.

If your cat has eaten too much garlic, they may become tired an uninterested in food. In extreme cases they may even faint. Other symptoms include red coloured urine, vomiting, and diarrhea. In short, your cat will be having a very bad time and they will need an immediate trip to the vet for treatment.


Cats can eat small amounts of mayo but large or regular consumption may cause them discomfort. Mayo that contains a lot of lemon or garlic can be toxic to your cat, even in small quantities. If you think your cat has eaten one of these ingredients, or is clearly suffering after eating mayonaise, you should take them to a vet immediately.