Reasons Why Milk is Making Your Cat Sick

why do cats like milk

Cats like milk; that’s no secret, and in any cartoon featuring cats, you will see cats drinking big bowls of milk, and they seem to love it!

But why do cats like milk so much?

Cats like milk because, like all mammals, the first thing they ever drank was their mother’s milk. Therefore, it has a familiar taste to them. Milk is also high in fat and protein, which cats can smell and enjoy. However, after their breastfeeding period, there is no need for cats to drink milk.

Why do cats like milk?

As we all know, all cats are obsessed with milk, and yes, it definitely has to do with the fact that as a kitten, they drank their mother’s milk to grow strong. But that isn’t the whole story.

Cats like all dairy products and they will gather around as soon as you take the milk out of the fridge. But wait, they like all dairy products?

Yes, cats like milk, cheese, yogurt, and even ice cream. Anything that is based on milk is super attractive to cats. But why?

Cats can smell the fat and protein contained in milk and, therefore, in all milk-based products.

There aren’t many cats that will pass up on the chance to get a milky treat from you, even when they know it will make them feel miserable for the rest of the day.

Why cats shouldn’t have any milk products

What is that? Do cats get sick when taking milk products? Yes, they do!

Then you might ask yourself why are cats always depicted drinking milk? Well, liking something doesn’t necessarily mean that it is good for you.

The same is true for cats. All cats are lactose intolerant which means that their bodies, or rather their digestive system, cannot process milk products.

Being lactose intolerant is relatively common in humans as well. Like those of us who are intolerant, cats will get sick when indigestion anything that contains lactose, like milk or milk-based products.

How will milk products affect your cat?

Being intolerant is not the same as being allergic to something. If you are allergic to something, your body will react to that substance. That reaction remains, even when the substance is already gone from your system.

Being intolerant to something will make you sick when ingesting a substance, like milk. However, when the substance leaves your body, either by vomiting or via your feces or urine, the effects of the intolerance will be gone.

For that reason, a cat who got sick from drinking milk will feel much better after ejecting it from its body. 

So, after digesting milk, most cats will feel miserable and have belly aches. Its body will try to get rid of it as soon as possible. This can result in your cat vomiting or have (very smelly) diarrhea.

Most cats instinctively know that milk is not good for them, but most of them just cannot resist the urge to get some.

Why are all cats lactose intolerant?

Without going into too much technical details about what causes cats to be lactose intolerant (petmd.com did a great article on that), it is mainly caused by the absence of a specific enzyme in a cat’s digestive system.

To break down the fat and sugar that is present in milk, a particular enzyme called lactase is needed.

Humans (the ones that are not lactose intolerant) also possess this enzyme. However, in cats, this enzyme breaks down and stops being produced in their bodies after they stop breastfeeding from their mother.

This happens because nature decided that there is no need for cats to drink milk after their breastfeeding period. Humans are a bit weird in that regard because not only do we keep on drinking milk well into our childhood and most of us during our entire life, we are also the only mammal that drinks the milk of another mammal.

It’s strange when you think about it.

Anyway, humans have evolved to keep producing this breaking-milk-down-enzyme, and cats haven’t.

Should I stop giving my cat milk or milk products?

Since cats cannot digest milk and make them feel sick if they try, it is best not to feed your cat any milk-based products. No matter how much they want it, this is one of those occasions that (cat)-parents know best. 

Cats should drink water to hydrate, and there is no need to introduce other choices into their diet.

Stop feeding your cat milk or other treats meant for humans if you care for its wellbeing. If you really have to, or just want to treat your cat every once in a while, do so in moderation. One small piece of cheese or a few licks of milk won’t directly hurt them, but moderation is key.

On the other hand, there are plenty of alternatives available that are not harmful to your cat.Several cat food brands carry special cat milk with lactose and other harmful components removed. 

Better to treat your cat with a snack that is intended for cats

Final thoughts

It’s not so strange that cats like milk, even though it’s not good for them when you think about it. I mean, we as humans know a lot of things are not good or healthy for us, and we still consume them.

But seriously, in the end, it all comes down to moderation. If you give your cat a slice of cheese or a few spoons of milk every once in a while, she’ll probably be OK.

Our advice would be to avoid it if you can or replace it with a product intended for cats, like special cat milk. 

In any case, with any food, you give your cat, monitor how they respond. If your cat gets sick after drinking some milk and has to vomit, it probably best to avoid milk or milk products altogether. 

Tom Alexander is a life-long cat parent and enjoys sharing a home with his cat Max and his family. Being a devoted cat person, his passion for everything feline and blogging is the driving force behind catnfriends.com. As the founder and editor at Cat & Friends, Tom aims to provide an interesting and great resource for cat owners.

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