Have you ever wondered if you actually swallow eight spiders as a year in your sleep, as the old wives' tale suggests? Well, you can rest assured, knowing that it's not (likely) going to happen — at least not in the way the myth suggests.

"Bugs are biologically wired to stay alive, not to walk into peoples' mouths and be accidentally eaten," health expert Jaya Jaya Myra tells Bustle. "While it's possible we can eat bugs in our sleep, actually doing it seldom happens."

That doesn't, however, mean you get away scot-free when it comes to munching on insects. "Throughout the year, we are unknowingly eating hundreds of insects/parts in our food products," Siobhan O'Grady, co- founder of Findatopdoc.com, tells Bustle. "We know this to be true because the FDA has established a handbook and guide which actually points out the 'acceptable' number of insects/insect parts allowed per food item. An example being; per 100 grams of peanut butter, a manufacturer is allowed to have fewer than 30 insect fragments."

No need to panic, though, as it's just a typical part of life. "The hard truth is that no matter how clean a food or packaging facility may be, insects find their way in," O'Grady says. "Because of this, the FDA has developed standards for the acceptable bug consumption per product. So the question is not if you eat bugs... it's how many!"

We've all heard the health myth that if you swallow gum, it will sit in your stomach and take seven years to digest. But while anything's possible, the only time gum tends to stick around is when it's larger than a quarter. (Which is a lot of gum to swallow in the first place.)

"After having seen hundreds of stomachs, I can say that if you swallow gum, it will not stay in your stomach for seven years as the popular myth describes," Dr. Sarina Pasricha, MD, MSCR, a Harvard-trained double-board certified gastroenterologist, tells Bustle. "The only time that you may see gum in the stomach is if the gum wad is so large (larger than a quarter) that it gets physically stuck or trapped in the stomach causing a blockage." But again, that's quite rare.

More often than not, gum passes right on through. "Gum is quite resilient and swallowed gum is unlikely to get broken down or digested by our normal gut enzymes," Dr. Pasricha says. "However, the natural motility of the gut will move the gum through your stomach, small bowel, and colon until you eventually poop it out. Gum will essentially pass through your body undigested in its original form. Gum should typically pass through your body in about 48 to 60 hours."

Have you or your partner ever wondered about that myth that hot tubs can lower sperm count? Well, there may be some truth to it. Back in 2007, the University of California conducted a study on men who spent about 30 minutes per week soaking in hot tubs or hot baths, and found that all the men showed "signs of infertility, with impaired sperm production and motility."

There is good news, though. Once the men stopped soaking in hot water, half experienced “a mean increase in total motile sperm counts of 491 percent after three to six months.” So if you're trying to conceive, hot tubs may be something to use less often.

This one is super gross, but there's a myth floating around that "your mouth is dirtier than a toilet seat" — meaning, it has more germs in it than the average toilet might have on its rim — and it has some truth to it.

"While it is difficult to actually measure the amount of bacteria in an average mouth, it is fair to say that they are pretty filthy," Dr. Ron Baise, owner and head dentist of 92 Dental, tells Bustle. "Other than a small window of time after brushing, teeth are permanently covered in a thin film of bacteria called plaque. This film is sticky and can cover all areas of the mouth. As the mouth is warm, wet, and has a constant oxygen supply, the bacteria in this plaque multiply super quickly. When this plaque mixes with saliva it also hardens and becomes near impossible to remove."

And then, there's the whole business of your gums. "Almost everyone has some degree of gum disease in their life," Dr. Baise says. "Gum disease is your gum slowly rotting away. It is the leading cause of tooth loss and bad breath. This means you have rotting flesh in your mouth most of the time. If you ever smell the stuff that comes out onto your floss you will know what I mean."

But as long as you're brushing and flossing, and getting regular dental checkups, it's nothing to worry about. We all have mouths dirtier than toilet seats. And that's a-OK.

If your grandparents ever warned against watching too much TV, saying it'll damage your eyes, they may have been onto something.

"The problem with TV and computer use is when you’re using for long periods of time," Dr. Nichole Moos, OD and VSP network optometrist, tells Bustle. "There’s blue light that comes off of the computer and it’s been correlated with more eye fatigue at the end of the day."

While starting at a screen might not cause permanent damage to your eyes, it is smart to give your eyes a rest, and take other preventative measures. "There are certain lenses and coatings [for eyeglasses] that can help to reduce some of that digital eye strain that you might experience by filtering out different levels of blue light," says Dr. Moos. "Another great tool to use at work, if you’ve been sitting at a computer all day, is the 20/20/20 rule. So every 20 minutes, take a 20 second break, and look 20 feet away." Do that, and your eyes will thank you.

They say "you are what you eat," so it stands to reason that the myth about eating too many carrots, and getting orange skin as a result, might have some truth to it.

As it turns out, if your diet is chock full of bright, orange carrots — or other foods rich in beta-carotene — it can actually start to tint your skin a slight yellowish shade, according to the Dermatology Clinic at UAMS. This condition, called "carotenemia," isn't dangerous. But it might make your palms and the soles of your feet a bit orange.

You have to eat a lot of carrots for this to happen, so don't avoid them for fear of turning orange. And for anyone who does end up with carotenemia, the course of treatment is to just eat a low-carotene diet, until it goes away.

There are so many old wives' tales about sneezes, and what they may or may not do to your body. Some say you shouldn't hold a sneeze in, since doing so can damage your neck, while others say your heart stops when you sneeze. And both claims have been shown to have some truth to them.

There's also the scary notion that sneezing can cause you to have a stroke. According to UC Irvine Health, most sneezes and coughs pose no problems other than the fact they're likely to be accompanied by other annoying symptoms, such as a runny nose.

That said, in some rare instances, sneezing can cause a stroke. According to UC Irvine Health, "If you have high blood pressure or have been diagnosed with a cerebral aneurysm (a weakened blood vessel in the brain that could rupture under pressure), forceful coughing, sneezing, or blowing your nose could cause a stroke. This is because such actions may suddenly increase the pressure inside of your brain. So if you have a weakness in your arteries caused by high blood pressure or an existing aneurysm, you could experience a hemorrhagic stroke, where blood leaks into your brain."

Again, this is incredibly rare. So unless you have a diagnosed health condition, it's unlikely that a sneeze will lead to anything more than the need to grab a tissue.

It is interesting, however, to think about old wives' tales, and which ones may be true. It seems most start with a grain of truth, and research later uncovers the facts. More often than not, though, these old health myths are just not worth worrying about.