
Can cats eat mustard? Will it cause them any harm if they’ve licked or eaten some mustard?
If your cat took the opportunity in front of them to lick some mustard you’re right to be concerned.
Cats should not be eating any form of hot or spicy foods. If they’ve only had a little nibble, however, you shouldn’t have anything to worry about though.
My advice is to keep an eye on them for the next few hours.
There’s a chance they will have an upset stomach, which might result in diarrhea or vomiting. Anything symptoms more serious than this and you should seek the advice of your vet.
With this in mind, here’s everything you need to know about mustards and the potential problems this spicy condiment presents for pets.
What’s in Mustard?

Mustard is a condiment made from the seeds of a mustard plant. The type of seed largely determines the taste and strength of the mustard, but there are also other ingredients that go into the preparation.
Most of us are familiar with the yellow type we add to hotdogs or the side of our plate, but there are much more spicy and flavorsome variations. The brown deli-style mustard that’s also common across the US is a little spicier. There are also peppery and hot mustards that pack more of a punch.
If your cat has eaten some mustard, make a note of exactly which type they ate in case they experience some side effects later.
Is Mustard Bad for Cats?
While mustard isn’t toxic or poisonous to cats, it’s still not a good idea to let your cat eat it.
Most human foods and condiments, in particular, are not good for cats. There are preservatives, additives, and other ingredients that are very foreign to them that will almost certainly cause an upset stomach.
Cats are meat-eaters, and they don’t want seasonings, condiments, and sauces like we do when eating meat. In the wild, they eat prey they catch and get all the nutrition they need from their kills.
Their formulated foods you buy over the counter have been specially formulated to deliver all this nutrition without the need for a kill. So, while you can include some treats and different foods to mix up their diet and make it interesting for them, mustard shouldn’t be on the list.
White, Yellow, Brown, Black, Honey Mustard – All Are Bad
As I mentioned earlier, there are lots of different types, colors, styles, and strengths of mustard. The bottom line is that all of them are bad for cats.
The seeds in particular present even more problems for cats. So, if you have mustard seeds in your kitchen, keep these locked away somewhere cat-proof. Something like honey mustard might be even more appealing to a cat, so bear that in mind when leaving your plate unattended too!
Can Cats Eat Mustard Greens?

If you’re growing your own mustard plants you’ll be aware of another potential hazard – cats tend to munch on plant leaves.
The leaves of a mustard plant are called mustard greens. They’re packed with good nutrition for us and are used in various dishes. The same can’t be said for cats, however. Cats should not eat mustard greens, doing so will likely cause stomach upset.
What to Expect If Your Cat Eats Mustard or Spicy Foods
If you know your cat has eaten some mustard, you’re going to need to keep a close eye on them for a few hours. I’m not trying to scare you, it’s probably nothing to worry about, especially if they only had a little bit.
But it’s best to keep an eye on them. Cat’s are very good at isolating themselves when they’re feeling sick, so check on them.
You’ll likely notice your cat pawing at their face and licking a lot as they try to remove the taste from lingering in their mouths.
If you can encourage them to drink some water, that’ll help. But we all know how hard it is to encourage cats to drink. If they are pacing and acting restless, they probably have an upset stomach.
If you can get close and have a listen, you might hear some telltale gurgling or bubbling noises. This is a sign that something might come out of either end, so brace yourself with the cleaning products.
Diarrhea or vomiting should be the worst of it. As long as your cat has a drink and eats normally within a 24 hour period, their bout of the tummy rumbles should pass.
We can only hope they’ve learned a lesson!
In Summary – Can Cats Eat Mustard?
Mustard is not on the toxic or dangerous foods list for cats, but it’s best you keep all types of mustard well out of their way.
There’s no benefit to a cat eating mustard, there’s really only downsides. Even if they clearly like the taste and keep pestering you to have a lick, you’re best off making sure they don’t get their tongue on any.
Otherwise, you’re just going to aid them in getting a bad tummy, and that’s not nice for anyone.
How about your cats? Have they tried mustard or any other weird foods and condiments? Hopefully, they were fine, but feel free to share any stories you have below. Thanks.