Is milk truly bad for adult cats, and if so why?

Somehow our domestic herd (four head of cats) has become addicted to milk. We gave them milk once, and that was it, the milk monkey was on their backs. For about 2 months, we’ve been giving them small amounts of skim milk without noticing any ill effects. FTR, these are more or less middle-aged cats, ranging in age from 5 to 11.

Today I tried giving them “Catsip” milk substitute made specifically for cats, and they seem to like it, but it’s very expensive compared to regular milk. So, why is milk supposed to be bad for grown cats? I thought perhaps it was the calcium, that could lead to kidney stones, yet the Catsip box doesn’t mention calcium or kidney stones. So what’s the deal? How can a little calcium and casein be bad for a cat?

Here’s my take:

I don’t know that it’s particularly bad for cats, but I don’t think they get anything out of it. Somewhere along the line, people got the impression that cats should drink milk. Truth is, they’ll drink whatever they get, just like any other animal. The only species (as far as I know) that drinks milk as adults by choice is us. And we don’t even drink our own milk–we drink cow’s milk (and for the brave, goat’s milk). We just got it in our heads that we should be drinking a lot of milk.

However, as to whether or not it’s bad for them, I’m not sure. But it wouldn’t surprise me. I imagine cats would have a hard time breaking down the enzymes in cow’s milk (cows are born with 4 stomachs, if memory serves, to break down milk).

I’m sure someone will correct me if I’m wrong.

No cows have 4 stomachs to break down grass. ffs…

My guess would be for the same reason that most adult humans don’t drink it - they no longer produce the enzymes that the young of the species have which allow them to properly digest certain milk components, and may develop digestion problems (gas, diarrhoea, etc.) as a result. Most people of northern European descent continue to produce the enzymes into adulthood, but most people of other ancestries do not.

Adult cats don’t digest lactose well at all, and the undigested sugar tends to give them the shits, as BK has pointed out. In addition, the extra fat, cholesterol, and calories don’t do them a bit of good, even if it doesn’t do them any harm.

Catsip, as I recall, is essentially soymilk marketed for kitties. As such, it doesn’t have lactose in it, so it doesn’t give Fluffy the runs.

Small amounts is fine, even regular milk. And, there are lactose free milks for humans which are much cheaper than Catsip.

But again- with regular milk- it can be an occ treat, not part of his diet.

My cat will stalk and capture a live cow in order to obtain milk. Unfortunately, whenever she manages to get some from a glass left on the table, she immediately barfs it back up.

We have had many episodes of this, and she has gotten so good at it that we are thinking of applying to the Olympic Committee for an event called the “run and barf”, since this is what she does. Running and barfing leaves wonderful elongated stripes of puke all over the carpet. It’s especially gratifying if she has just eaten a generous helping of kibble, so that it stains everything a lovely shade of shit brown.

Cats+milk=mess

All mammals who produce lactose in their milk stop making the lactase enzyme that digests lactose at around the time of weaning.

This is also true for human-type mammals, although a large minority of them have the mutation that keeps lactase prouction going for their entire lives.

I told my ex, back before he was my ex, that if he EVER gave my cat dairy products, he’d have to clean the box afterwards. Oh my God, it was bad, the couple of times he got dairy.

We would give my cat milk on the occasions that he was fed indoors. He was mostly an out door cat, but in the winter would come in to eat and lay about in front of the fireplace. He would never drink it fresh, he would let it turn to yogurt then eat it. His bowl was right next to the hearth, and the milk would turn fairly quickly. Never had to worry about the litter box, he just went under the big spruce tree across from the kitchen door.

Should I have not given my cat, Jethro, that big bowl of heavy cream? He sure liked it!

Both of my adult cats finish off our cereal bowls without any problems. Well, sometimes the litter box is a bit stinky but I haven’t directly linked this to milk.

Is soya milk a good substitute then ?

Both my 15-year-olds lick out cereal bowls and yogurt and cottage cheese containers, with no problems whatsoever. Sometimes, even a little half-n-half for a treat. Just like us, they all have different tolerances.

How about your cats though? :wink:

So the bottom line seems to be: if it doesn’t make them barf or get the shits, it should be OK for them? Cool - Cookie Monster is in for a milky treat now… :smiley:

I wouldn’t even give it to kittens. When my friend got a new kitten years ago, she and her sisters were feeding him milk, and he kept having severe diarrhea-OUTSIDE of the litter box. She stopped giving him milk and the accidents stopped.

This should be determined on a cat-by-cat basis, clearly.

My vet tech said there’s no advantage to giving my cat milk, so why bother? I agree. He (the cat) enjoyed a good chin scratch much more, anyway.
I love simplicity.
Peace,
mangeorge