Most of the time, when thinking about what kinds of human foods are safe to give to our cats, we’re considering actual foods, not condiments like mayonnaise or ketchup.
We should know the relative safety of sauces and dressings in case our feline friends manage to get their paws on them. Is ketchup, for example, good for them to eat?
To put it briefly, nope! Ketchup is not good for your cat’s health, so stop feeding it to it. However, why is it so terrible?
Can Cats Eat Ketchup?
There is no simple answer to the question of whether or not cats can safely consume ketchup, but the consensus seems to lean against it.
While a small amount of ketchup probably won’t hurt your cat, there are some ingredients in ketchup that could be harmful if your cat ate enough of it.
Is Ketchup Healthy For Cats?
There are many ingredients in ketchup that are bad for cats and one or more could be toxic to them.
Garlic and onion powder, two of ketchup’s main ingredients, are toxic to cats and therefore should be avoided.
Alliums, of which garlic and onions are members, contain sulfur compounds that are poisonous to felines and canines.
Heinz body anemia (no, not named after the ketchup brand!) is caused by the sulfur compounds in foods belonging to this family when they are consumed.
Allium toxicity may be to blame for your pet’s jaundice, lethargy, diarrhea, and loss of appetite. Additionally, garlic is roughly five times as lethal to cats as onion.
Ketchup contains a lot of sugar and artificial sweeteners, both of which are bad for your cat. These components aren’t harmful per se, but they also aren’t particularly helpful.
Cats are susceptible to the same health problems that humans are, including weight gain, periodontal disease, diabetes, and more, when they consume sugar. In addition, sugar is difficult for a cat’s digestive system to process because cats rarely eat it.
No artificial sweeteners, including those found in ketchup and other processed foods, are safe for cats.
Even though there aren’t many studies documenting this, it’s possible that xylitol poisoning can cause seizures, liver failure, and death in cats, even at low doses if not treated promptly.
Last but not least, the salt content of ketchup is relatively high. A cat can get salt poisoning from eating as little as 0.05 tablespoons of salt, so don’t let them get their paws on any.
As little as three hours after ingestion, symptoms such as vomiting, tremors, lethargy, and disorientation can appear due to salt poisoning.
Cats shouldn’t eat ketchup because it’s extremely unhealthy for them. Don’t freak out if they manage to get a few bites in, but prevent them from devouring the whole thing!
Why Cats Shouldn’t Eat Ketchup
Even though cats shouldn’t eat ketchup, it’s probably fine if yours has gotten a lick or two. When they get more than a taste, that’s when things turn bad. What gives?
Ketchup may be made with tomatoes, but it also contains sugar, vinegar, and other ingredients that are bad for cats. Garlic and onion powder, both of which can be found in ketchup, are poisonous to cats.
If your pet eats garlic or onions, they may develop Heinz body anemia, which is a form of red blood cell damage. Loss of appetite, weakness, skin discoloration, fever, and other symptoms are all associated with this illness.
The high sodium content of ketchup is also bad for cats. Ingesting too much salt at once can cause your cat to become dangerously dehydrated, prompting it to drink excessive amounts of water until it vomits.
Even worse, they run the risk of developing hypernatremia, also known as salt poisoning. Some of the symptoms of salt poisoning include extreme thirst, convulsions, mental confusion, nausea, and vomiting.
Get your cat to the vet ASAP if you think it may have consumed too much salt.
However, there is more in ketchup that could be harmful to your cat. Another culprit is sugar.
While felines can safely consume sugar, their digestive systems have more trouble processing it because they are carnivores and rarely consume carbohydrates. And just like in people, too much sugar can cause health problems like diabetes.
Ketchup, being a processed food, may have artificial flavorings, colors, and sweeteners; these are all things that cats should avoid.
Some brands of ketchup include the sugar substitute xylitol in their ingredient list. Unlike in canines, it doesn’t cause the same toxic effects in humans.
Ketchup, as you can see, poses no benefits to your cat’s health and may even cause illness if consumed in excess.
What Happens If My Cat Eats Ketchup?
Lucky for us, most felines won’t want more than a taste of ketchup. That much ketchup shouldn’t be dangerous, either.
However, if your cat suddenly develops a taste for ketchup, you should keep it out of their reach.
Symptoms like diarrhea and vomiting are common in people who eat a bit more than they should. In a day or two, however, these issues should disappear on their own.
Get them to the vet ASAP if they don’t, or if you notice any other symptoms like tremors, loss of appetite, jaundice, or disorientation.
Your cat may have overindulged in ketchup and be experiencing the toxic effects of the garlic, onions, or salt.
What To Do If Your Cat Eats Ketchup

Don’t freak out if you find that your cat has licked some ketchup off your plate. Ketchup shouldn’t be dangerous in small amounts.
When your cat gets their paws on a lot of ketchup, like when a bottle gets knocked over and they eat all the ketchup that spilled out, that’s when you should be worried.
If your cat ingests any amount of ketchup, large or small, it is important to watch for symptoms such as vomiting, diarrhea, loss of appetite, and dilated pupils.
In addition to the aforementioned symptoms, anemia can also cause fatigue, fever, and skin discoloration. Get your cat to the vet as soon as possible if you notice anything unusual about its behavior or health.
Can Cats Eat Tomatoes?
Since tomatoes weren’t specifically called out as being harmful to cats, you may also be wondering if you can feed them to yours.
Toxicity to cats is limited to the plant itself; ripe tomatoes are safe and even beneficial because they contain vitamins and minerals.
But rather than supplementing their diet with human foods, it’s best to feed your cat food made especially for them.
You should talk to your vet before giving your cat any human food, including a ripe tomato.

Conclusion
Cats and ketchup don’t go together like peanut butter and jelly. Ketchup has many ingredients that are harmful to cats, including garlic, onion, salt, and sugar, and should be avoided at all costs.
You should keep your cat away from ketchup because it can cause anything from mild stomach upset to death.
They should be fine if they manage to sneak a taste, though, as long as it’s not too much. Please have your cat examined by your vet if you notice any signs of distress after it has consumed ketchup.