With the day of love coming around the corner, it never hurts to bone up on some of its bare essentials. I’m talking, of course, about sex.

So let’s go ahead and take a look at some of the most pernicious and enduring myths surrounding sex. Though Medical Daily has certainly covered popular misconceptions about the subject before, we’ll strictly be honing in on its physiological aspects this go-around, aka how the body normally functions when it comes to sex.

[Related: Should Doctors Do Virginity Tests?]

#1 - Virginity Is A Thing

This particular idea has been debunked aplenty, including by Medical Daily’s own Sabrina Bachai, but it’s worth shouting out into the void until the heat death of the universe, given how poisonous it is: There’s no such thing in biology as virginity.

That doesn’t mean we don’t ascribe a whole smorgasbord of stereotypes onto people who haven’t had sexual intercourse, but these are entirely based on our surrounding culture and society. Even the very concept of sexual intercourse is vague and generally heterocentric (are lesbians who never had penetrative sex with a man virgins?)

The clearest present example of how useless it is to medically define virginity is with the hymen, the membrane that wraps around (but usually doesn’t block) the vaginal opening. First things first, not all women are born with a hymen, but even for those who are, sexual intercourse isn’t the only reason why it “breaks” — even inserting a tampon or exercise can do the trick. Breaking is really the wrong word to use here, since it’s more like a gradual stretching that can occasionally lead to a partial tear.

[Related: 5 Weird Things That Shouldn't Cause Orgasms, But Do]

Though the hymen is thickest in a girl’s youth and gradually thins as she ages and moves about, there are still plenty of older women who have partially intact hymens. Likewise, the hymen is often thought to be the reason why women either have pain or bleeding during their first time, but that doesn’t have to always be the case, provided there’s a modicum of preparation (aka lubrication, foreplay, and an attentive partner). And of course, bleeding during sex can happen even after you’re no longer a “virgin.”

Quite simply put, there's no way a person, even a trained medical professional, could look at a woman's hymen and be able to reliably determine their sexual history.

#2 - Smegma Is Disgusting (And Worthless)

As previously detailed by yours truly, smegma is traditionally known by a much less flattering name: dick cheese.

That’s because smegma is most prominently recognized as the byproduct of an unwashed penis — every bit as foul smelling and repugnant as its human source. In reality, smegma is naturally produced by every girl and boy mammal in the world, though it’s most readily found in uncircumcised young men.

The oily and clear discharge is regularly released from our genitals in order to serve as homemade lube, making for a smoother, sexier time. But when this discharge isn’t properly cleaned (with warm water, not soap), the fatty oils become mixed with dead skin cells and fed upon by bacteria, making it opaque and smelly, similar to how body odor is made. Smegma’s bad rap then is mostly the fault of ignorant or unwilling young men who don’t pull back their foreskin when cleaning, since that’s where it accumulates in men.

Otherwise, though, smegma is an essential and welcomed part of sex, so embrace it.

[Related: 8 Little-Known Facts About Male Ejaculation]

#3 - Aphrodisiacs Exist

Let’s be clear here: I’m not saying a well-scented room or particularly tasty box of chocolates can’t rev your engines up — mentally. After all, the experience of arousal is just as grounded in our emotional state as it is our physical sensations. And obviously, there are chemical substances that improve our sexual functioning (Viagra). What I am saying that the most common perception of aphrodisiacs — as foods and drinks that naturally and biologically ramp our sexual desire — isn’t supported by the available evidence.

That hasn’t stopped researchers and the media alike from trumpeting the opposite though. You won’t have to go too far onto Google to find a list of “Natural Foods Guaranteed To Improve Your Sex Life!” staring at you from the computer screen. Let’s be generous and call most of these items a far reach (Bananas are rich in potassium, which helps build muscle strength! Which is great for sex! And every other task performed by people!).

[Related: 5 Everyday Foods That Can Kill Your Sex Drive]

Still, there are a few bits of shaky research that claim to prove the power of aphrodisiacs. Take for instance a 2006 Italian survey that showed women who loved chocolate were slightly more likely to report better sexual function. Trouble is, once you accounted for age (young women were more likely to enjoy chocolate), that difference vanished.

Another study in 2005 injected rats with two non-essential amino acids and found they boosted the rats’ testosterone and estrogen levels. The authors then found a rich source of the same amino acids inside mussels and clams, close cousins of the oyster, a well-known aphrodisiac. Leaving aside the fact they didn’t actually study either people or oysters, the research was ultimately never published, making it the equivalent of a scientific folk tale. Coffee? Nope. Most any herbal supplement? Nah.

Sorry, guys and gals. Looks like you’ll have to charm your way into your beloved’s bedroom by playing to their personal preferences and not their biology.

#4 - Sex Is For The Young'uns

This one’s really a myth for the people who haven’t reached their mid-to-golden years. But yes, the only partially correct idea that our sexual peak is found in our youngest years (30s for women, early 20s for men) is one that’s continuously skewed our public discussion of sex.

[Related: What Your Penis Foreskin May Say About Your Health]

The belief is centered around the reality that our respective sex hormones, testosterone and estrogen, fluctuate as we age. For men, the highest levels are found in our teen years, while women’s estrogen levels begin peaking around the low 30s, as they’re starting to approach menopause. Our hormones do certainly influence our sex lives, and there’s research showing women are more likely to be into sex right around that same time window.

The wrinkle here is the overall decline in sexual desire and functioning as we age isn’t really as substantial as we make it out to be. That’s because, as I alluded to earlier, the strictly physical isn't entirely what makes sex enjoyable. Our sexual wants and fantasies are carried safe and sound in our noggins no matter how old we get. Likewise, sex hormones are only part of the biological puzzle that primes us for pleasure (neurotransmitters such as dopamine are involved too). Lastly, with the advent of drugs like Viagra and hormone therapy for women, sex doesn’t need to have an expiration date.

Case in point, a 2015 study found that up to 54 percent of men and 31 percent of women in their 70s and 80s reported having sex at least twice a month, reaffirming previous research.

[Related: The Science Behind 'Use It Or Lose It']

“I think from our point of view it suggests to the health professionals not to just assume that they would necessarily be sexually inactive,” David Lee, the study’s lead author, told Medical Daily at the time. “There may be a health care need in terms of extending, and not just ignoring, people’s sexual health and well-being.”

In other words, don’t let a silly little thing like the number of candles on your birthday cake get in the way of seeking out an enjoyable sex life. On a similar note, don’t mistakenly assume that just because you might not have to worry about pregnancy anymore, STDs aren’t a risk either. They definitely still are.