Animals are weird. Yeah, humans are animals, too and yeah, we're weird, but we have our own social conventions that most of us follow. One of those conventions: Don't sniff other people's armpits, as a general rule. Cats either didn't get the memo or don't care though, because some of them are very into armpit-sniffing as a pastime. If your cat is in this category and you often find yourself thinking, "but WHY?), keep reading. Here's everything you need to know about what's behind cats' weird love of sniffing armpits.
How good is a cat's sense of smell?
Are you thinking, "Well, maybe cats just have really terrible noses and don't realize that they're inhaling big wafts of B.O.," then think again. Like most animals, cats have excellent sniffers (there's even some anecdotal evidence of cats sniffing out cancer in their owners).
In fact, according to 2017 paper published in the journal Applied Animal Behavior Science, cats have better "olfactory discrimination" than dogs do. Kristyn Vitale Shreve, who co-authored the paper with Monique Udell, believes that this ability might make cats even better at sniffing out these things than dogs are: "Given the importance of olfaction in cat sensory perception, cats could be trained to discriminate between a variety of odors, therefore serving in working roles for detecting specific humans, medical scent detection, bomb sniffing, or drug sniffing."
So the short answer is: Cats have a really, really good sense of smell.
If they can definitely smell your potentially less-than-pleasant armpit smells, then, why are cats sniffing there. There are a few possible reasons.
Your cat might like the smell of your armpits
Our armpits have apocrine sweat glands, which produce the really pungent sweat that tends to be secreted in that area. As a result, armpit sweat is full of fats and proteins that cats are attracted to. Basically, your cat might think your armpit smells kind of tasty. Yep, it just got even more gross.
Your cat might be telling you that you stink
Next time your cat sniffs your armpits, pay attention to what happens next. Does your cat just sniff and go or does she engage in some head butting? If it's the latter, your cat might actually be trying to cover your scent with hers in a not-so-subtle attempt to get rid of a smell she doesn't love on a person that she does love.
"They're saying 'I love you. You're so wonderful but you're also a little stinky. Let's get you smelling like us,'" Ingrid Johnson, a certified cat behavior consultant who has been featured on Animal Planet, told PetMD.
Why armpit-nuzzling cats might miss their mommies
Another potential cause of your cat's armpit-nuzzling behavior? She could just really miss her mom, especially if the cat in question is a kitten or was separated from its mother too soon. If this is the case, however, the sniffing would likely give way to nipping and trying to suckle or nurse from the armpit area.
And, if the armpit sniffing turns into licking but not suckling? Well, that could just be your cat craving salt, which is abundant in human sweat.
"If a cat is licking under your arm, it could be seeking the salt that exudes from our bodies in the form of sweat," Joan Morris, the pets & wildlife columnist for the Bay Area News Group, wrote. "Cats can have a strong desire for salt."
There are several reasons why your cat might sniff your armpits, and none of them are reasons to worry (except that you might be mildly stinky). Just relax and enjoy the sniffing process.