There are some things about sex that we all know: get consent, use protection, make sure your partner enjoys themselves as much as you do. But, what about what we don't know? Could it HURT US? Don't worry, this r/AskReddit thread is a cornucopia of sex facts that you probably didn't know (and probably don't really to know)! It's always better to be SAFE!

1. You can trigger a severe allergic reaction in your partner with your junk! As if dating wasn't scary and horrible enough, there are actually allergens that can be spread via sexual intercourse! Well, actually, there's only one (that scientists are aware of!!!!). And it is NUTS! Specifically, brazil nuts.

If you're allergic to brazil nuts and have sex with somebody, who just ate some, you might have an allergic reaction. It's the only sexually transmitted allergic reaction we know of (so far).

via Erft


2. Sex cells are basically the Guinness World Record holders of the human body. Picture egg cells as the World's Heaviest Person, and sperm cells as...uhhh...World's Lightest Person? Close runner ups in each category are fat cells (ironic!) and red blood cells, respectively. Bodies are so gross and weird!!

The female egg (ovum) is the largest cell in the human body, and sperm are the smallest cells in the human body.

via cavdaddy69


3. We all know that the only evolutionary reason sex exists (and actually the only reason any living thing exists, but let's not get too cynical here...) is to make lil BABIES. Turns out: the most likely time to make a BABY is when someone who's just had a BABY participates in the BABYmaking act. UGH I'm buying condoms just thinking about it!

That it's much easier to conceive, and women are much more fertile, when they've just given birth. Loads of people think "hey ho, her period hasn't started again yet, let's go for it," hence loads of siblings born a year apart.

via PJM1990


4. Did you know that baby batter is actually baby DATA?! You read right: a single sperm contains juuust about 37.5MB worth of data. That means the average ejaculation would technically all fit into an inexpensive external hard drive (we don't recommend trying that at home!)

When you cum you are transferring 1.5 Terabytes of data.

via UnwrappedTrump


5. Speaking of cum being waaaay extra, it's been calculated that ejaculate leaves your body faster than your gramma drives. Slow down, little guys! We're all going the same place! Also, apologies for using the words 'cum' and 'your gramma' in the same sentence!!!

The average speed of ejaculate is 28mph, making it illegal in a school zone.

via fluffykitty12


6. Some people say men think with their, well, smaller heads. But, as it turns out, their smaller heads don't associate with their brain at all!! While male sexual arousal may be heavily linked to visual stimuli and brain responses, the *AHEM* final result of male arousal is actually controlled by a different area of the body completely. The Headless Horseman could actually still ejaculate, so to speak! 

The part of the body that controls ejaculation is not actually in the brain, its in the spine. A dude who gets decapitated can still ejaculate.

via Limfao93


7. If you've ever watched the Maury Show with any kind of frequency, than you probably already know about this one (it's happened twice!!!). The odds are astronomically small, but a woman can be be pregnant by different men at the same time! But only if her ovaries have released two eggs at a time, which actually happens kind of a lot!!! Terrifying!

Twins can have two different fathers.

via xmagusx


8. Are you a straight guy? If so, are you a boob guy or a butt guy? If you chose boob guy, there are some scientists out there that say YOU'RE WRONG!!! There is a theory in the scientific community of people who study tits (dream job?) that asserts that the reason human males are attracted to breasts has to do with the fact that our evolutionary ancestors LOVED ASS.

Evolutionary biologists speculate that the male fascination with female breasts is a carryover from when we, like nearly all mammals, always did it doggy style. The curves of the breasts mimic the curves of the butt cheeks.

via minpinerd


9. You know how sometimes guys classify themselves as either "growers" or "showers"? It turns out women can now join the ranks of people who do this! If they want to, which I suspect most don't.

The average vagina is about 3 inches deep, stretching to about 9 inches when fully aroused.

via shiftynightworker


10. Sex can actually be more dangerous than people think!!

Condoms don't really guarantee full protection when having sex. A friend of mine was wearing one and he got shot by the girls boyfriend...

via Youngilmour