However, neglecting your sheets for too long can result in some icky, unwanted guests– and I don’t mean the one-night mistake you made last Saturday. Here are the five nastiest things that should inspire you to grab the Tide and make a date with the washing machine.

1. Bed Bugs

Reports of bed bugs are rising on college campuses and even if you’re particularly clean, you may not be safe. The little bastards can catch a ride to your room on luggage, clothing, and old furniture (e.g. your hand-me-down futon). Plus, they can live up to a year without a feeding, so they could have been hiding out in your empty dorm room for the whole summer just waiting for you to move in and unpack. Luckily, pest control on college campuses is prepared to snuff the buggers via steam, extreme heat, or pesticides. If you wake up with little red welts from bedbug bites report it immediately before the infestation spreads down the hall.

2. Your Personal Sheddings

When we hit the sack every night, we shed dry, dead skin and hair. Gross. I gag at the site of a hair-clogged shower drain, and sleeping with hairballs seems just as unappealing. Girls with long hair shed a lot, so there’s also the chance that you’ve left your mark in your man’s bed as well. Of course, dead skin and strands of hair are a breeding ground for microorganisms, so bacteria can escalate after just a few nights of shedding in your sleep.

3. Bodily Fluids

Not only do we lose skin and hair while we sleep, but we also sweat every night. And that’s just one of the many bodily fluids that can collect in our sheets. We’ve all heard horror stories of hotels that don’t pass the black light test, but all of the things that go down in smarmy motels go on every night in college dorms, where there’s no maid service. Whether you’re snoozing in a sea of sweat or semen, or you are notorious for drooling on your pillow, soaking your sheets after a particularly hot night (or a hot one night stand) will flush out the bacteria.

4. Scabies

Another member of the bug family, scabies is caused by eight-legged parasitic itch mites. Though it is hard to catch scabies from brief physical contact, it is still possible to contract them from shaking hands or sharing infested bedclothes. Speaking of which, the most common form of transmitting scabies is through sexual contact, an act we all know runs rampant through college campuses. Scabies can produce small bumps or blisters, which are accompanied by relentless itching. Luckily, scabies can be treated fairly easily through mite-killing creams and sprays, and your sheets and clothes can be taken care of with one simple wash.

5. Whatever You’ve Been Carrying Around Campus

Good Morning America recently tested the sanitary habits of University of Maryland students. The students rubbed some lotions on to their hands and continued with their day. Hours later, the students’ hands were put through a black light test, which revealed how often the students had washed their hands after touching doorknobs, using the bathroom, eating lunch, and working on computers that thousands of other hands have touched. The black lights revealed remnants of the lotion around fingernails, crusted around bandages, and caked next to rings and watches. The lotion also proved to spread like bacteria, and showed up on clothes and other parts of the students’ bodies including near eyes and noses where infections could develop.

That said, all of the germs and bacteria you encounter each day as you trek from class to class sharing desks, computers, and books with hundreds of thousands of other students can ultimately end up in your sheets. Your bed is your final destination at the end of the day, so while it’s a good idea to keep your linens fresh, it’s also a good idea to go to bed clean yourself.