If you haven’t yet experienced the joy of walking into the bathroom to see your cat chowing down on an ear wax-covered cotton swab or a tissue you blew your nose on a few minutes earlier, just wait — it will happen to you someday. But why do cats seem to enjoy this stuff? In the end, like most other weird, cool and awesome things, it all comes down to science. Here are some things that gross us out when we see cats eating them, and why they’re so appealing to your feline friends.

1. Used cotton swabs

Why do your cats seem to have a taste for cotton swabs that you’ve used to clean your ears? It’s all about the ear wax. You see, ear wax isn’t really wax, it’s a special kind of sweat. Unlike the sweat that we excrete through most of our skin when we’re hot, ear wax is secreted by apocrine glands. In addition to water, apocrine glands add proteins and fats to the sweat — and cats just love proteins and fats.

2. Snotty tissues

There are few things less awesome than having to wrest one of your germ-laden used tissues from your cat’s mouth. Snot is made up of protein, sugar, dead skin cells, water and inorganic salts. If you have a cold, the snot will also contain bacteria and/or viruses and dead white blood cells. It’s my completely non-scientific hypothesis that the proteins and tissue salts in snot make it tasty for kitties. But don’t worry; human colds aren’t contagious to cats.

3. Your sweaty armpits

Like your ear canals, your armpits contain apocrine sweat glands, which is one of the reasons why armpit sweat produces body odor. The fats and proteins in armpit sweat can make it extra tasty -ÔÇô and if your deodorant contains lotion, that could contribute to the appeal. Of course, maybe your cats just want to groom the stink off you. By the way, your genital area also contains apocrine sweat glands, which may explain why dirty underwear is so attractive to some cats.

4. Used feminine hygiene products

Cats, being carnivores, enjoy the taste of blood. They’re also driven instinctively to clean up blood — whether the blood is on their prey, their muzzle after eating said prey, or a used feminine hygiene product — in order to avoid attracting other predators. (By the way, I once had a cat with a thing for digging used tampons out of the trash and enjoying a little nosh. It only took me one episode of this nasty behavior to invest in a cat-proof trash can.)

5. Other cats’ vomit

If you live in a multi-cat household, you’ve probably seen it: One cat heaves up her meal, and before you can even say "Aww, hell no," the cleanup crew sweeps in to take advantage of this gustatory largesse. While this keeps you from having to do a job that probably makes you want to vomit, it’s still pretty gross to watch. But why do cats do this? Simple: The food tastes good. This is especially true if you’re feeding canned or raw food. As an extra bonus, it’s been warmed up to body temperature and garnished with stomach-snot.

What other gross things is your cat attracted to? Do you have other ideas why nasty things are attractive to cats? Share your thoughts in the comments!

Read more cool facts about cats:

• 7 Crazy-Cool Facts About Feline Evolution
• Adult Acne is Not Just for Unlucky Humans — Cats Get Zits, Too
• 5 Ways Cats Are Weird About Water
• 5 Fast Facts About Your Cat’s Claws
• 5 Awesome Facts About Your Cat’s Tongue

About JaneA Kelley: Punk-rock cat mom, science nerd, animal shelter volunteer, and all-around geek with a passion for bad puns, intelligent conversation, and role-play adventure games. She gratefully and gracefully accepts her status as chief cat slave for her family of feline bloggers, who have been writing their cat advice column, Paws and Effect, since 2003. JaneA dreams of making a great living out of her love for cats.