Do you kiss your dog?

Find out how gross your questionable habits really are, according to health experts

I admit it, when it comes to food, I have some eeew-inducing practices, like skimming mold off old cheddar and feeding the rest to my unsuspecting family. We’re still alive, so how bad can it be? Because our gross human habits fall somewhere along the spectrum from mildly cringeworthy to full-on repulsive, I reached out to experts to find out where some common behaviors land on the gross-o-meter.

Eating old food:

The stamped expiration date—and its confusing cousins “use by” and “best before”—should be but one tool in your hmm-should-I-eat-this? toolbox. “With the exception of infant formula, food labels aren’t standardized or regulated,” says nutritionist Marie Spiker, an assistant professor at the University of Washington. “Few are related to biology or food safety—just peak freshness.” And so, she says, it’s totally fine and safe to eat foods that are not at their exact peak.Handling, packaging, refrigeration and storage all affect any food’s farm-to-plate timeline, so your best tools are your eyes and nose. “Most of the time, this is intuitive,” says Spiker. “If it looks good and smells good, it’s probably good.” Not sure? Consider this: “Spores spread through soft, porous surfaces. So in general, hard foods are more difficult to permeate and therefore safer to eat,” she says. Don’t trust your sense of smell or sight? Check out the FDA’s website, where food safety guidelines are available. So you probably should toss the whole package if you spot mold on bread, soft cheeses like Brie and feta, or soft produce such as strawberries. But it’s not too gross to slice off the funky stuff and save the rest of potatoes, cured meat like salami, or hard cheeses like my beloved cheddar.

Borrowing a toothbrush:

Most of us would never use a stranger’s toothbrush, for two good rea- sons: 1) We have no idea what illness or germs that person harbors; 2) It’s dis- gusting. But that’s surely not the same as borrowing your partner’s in a pinch, right? After all, we swap kisses. Welllll … “Your mouth is not a sterile place, and it’s full of bacteria unique to you,” says Matthew Messina, DDS, clinic director at Ohio State Upper Arlington Dentistry in Columbus. “The whole rea- son we brush and floss is to collect and remove live bacteria.” Often, it’s from spots that lips don’t touch. A cold, the flu or even herpes can be easily passed along on a toothbrush, especially if you have gingivitis or bloody gums. Using your partner’s toothbrush means you’re transferring their germs into your mouth, which can disrupt your own mouth’s delicate bacteria balance. Of course, if you’ve lived with some- one long enough, chances are that “your family group already shares some bacterial commonality,” says Messina. But it’s best to play it safe. If you find yourself on vacation without a toothbrush, just gargle with mouthwash or water. And he adds, when you’re traveling, remember: “Unless you’re on safari, toothbrushes are readily available. Just call the front desk.”

Kissing your dog:

Pet owners are shameless when it comes to showering their fur babies with affection. A recent survey revealed that 61% of dog owners admit to kissing their dogs on the mouth. All this despite the possibility of zoonotic (animal-to-human) diseases, including pasteurella, which can result in skin inflammation and joint infections; salmonella (stomach cramps, fever) and E. coli (diarrhea, bloodstream infections). That said, the risk of Spot passing you a parasite or anything else is very low … except when it isn’t. “If you’re young, old, pregnant or immunocompromised, if you have bad acne or psoriasis or an easily infected open wound, I’d avoid being licked on the face,” advises veterinarian Scott Weese, chief of infection control at Ontario Veterinary College. Even the healthy should pick their pecks wisely. Keep this in mind before planting a wet one on your dog: Everything they’ve licked — everything! — may end up inside you. That said, “There’s a cost-benefit analysis to be made,” says Weese. “For lots of people, kissing is a part of bonding with their pet. If that’s you and the risk is worth it, that’s fine.”

Sipping from unwashed water bottle

It’s highly likely that buried in a gym bag or forgotten in the car trunk is a reusable water bottle that’s been rinsed, rarely and barely, but never properly scrubbed. So what, it’s just water, right? Wrong! It’s a bunch of other things now too. The inside of your bottle is like a dirty aquarium. It’s “covered in biofilms, clusters of viable microorganisms growing from your mouth’s backwashed flora,” explains Peter C. Iwen, professor at the University of Nebraska’s department of pathology, microbiology and immunology. A small consolation: “Your own flora doesn’t necessarily hurt you.” What can hurt you, however, is any foreign bacteria—maybe you use a dirty barbell, wipe sweat off your lips, then take a drink—that can sneak into the bottle and multiply. A water bottle sitting a few hours in a warm car makes a nice petri dish for bacteria to thrive, and in “just water,” there are plenty of nutrients from your backwashed saliva for slimy biofilm to feast upon. A simple wash doesn’t clean this out. That’s because your bottle has a ton of microscopic crevices for bacteria to hide and grow into mold, which can cause diarrhea, vomiting or allergy symptoms. Porous plastic bottles are the most hospitable to bacteria, so opt for glass or stainless steel instead. But whatever you’re drinking from, try to wash it every few days with dish soap or, better yet, 1 part vinegar and 3 parts water.

Skipping the soap

Most of us tend to be fastidious when washing our hands in a public wash- room. But at home? Why bother with all that scrubbing? After all, the germs in your bathroom likely belong to you anyway. And you’re right, to a point. “Your immune system is trained to recognize your own microbes and get rid of the rest,” says Shannon Manning, associate professor of microbiology and molecular genetics at Michigan State University. But consider that a flushed toilet, when left open, expels invisible particles into the air at more than 6 feet per second. Just assume you’re going to get covered in some of that spray. “If you pick up a pathogen (an organism causing disease) on your hands and then, say, bite your nails or eat a sandwich, you can ingest the pathogen,” says Manning. And should that happen and you get sick, “Even microbes you already harbor can balloon if your immune system is busy fighting something else.” Hence the necessity of a good wash, preferably with antimicrobial soap. A simple splash of water is not only insufficient, but might be worse than not washing at all, says Manning, since foreign germs are more likely to stick to wet hands.

Tinkle in the shower

Relief for secret shower tinklers: Peeing while you’re in there is actually pretty natural. “Warm, running water from the shower stimulates the bladder to want to contract,” says Lori Lerner, associate professor and chief of urology at Boston University’s Chobanian & Avedisian School of Medicine. A sudden spasm can force urine from the bladder, and luckily there’s no need to fight the inev- itable. “In most cases, urine is sterile. It’s just electrolytes from your own body and it’s going right down the drain,” Dr. Lerner says. But what if you’re swimming in a public pool? OK, yes, other people’s pee is a pretty gagworthy thought, though, again, not quite as bad as it sounds. “Urine in a pool is very, very diluted with tons of chlorine for this exact reason,” says Dr. Lerner. Human bodies are leaky, and while technically any bodily fluid could contain disease-causing bacteria, if the risk of pool pee were anything but minuscule, you’d read about thousands upon thousands of infections daily. Far worse than the chemical-treated pool, adds Dr. Lerner, is a lake filled with fish waste and bac- teria. But thanks to nice scenery and nature’s good PR, nobody really frets about that.

Pimple Popping

Are you hooked on popping zits? Whether you’re doing it out of boredom or vanity, or for the dopamine hit (gross but true; your brain rewards this bad habit with a flood of happy hormones), you’re not alone. The proof: the TV show Dr. Pimple Popper and endless TikTok videos. But before your face ends up resembling an exploded minefield, Idaho-based, board-certified dermatologist Dustin Portela wants you to remember this: A popped pimple is basically an open wound where bacteria can sneak in and cause a highly contagious skin infection, like impetigo, or a yeast- based fungus, like candida. Dr. Portela has seen popped pimples snowball into painful infected abysses requiring antibiotics and surgical drainage. But good news: The likelihood of this is low. So if you can’t keep your fingers off your face, Dr. Portela suggests you scrub up like a surgeon. It takes two to five minutes to carefully scrub the hands and forearms with an antimicro- bial soap, according to the National Institute for Health. Even then, Dr. Portela warns, “infections still happen.” That’s why he suggests you don a pair of latex gloves, and, as soon as you’re done, apply a medicated pimple patch to help the picked-at lesion heal more quickly and to keep you from digging at it some more. Because the more you pick, the more likely you’ll scar.