It’s tempting to watch your best friend pull her favorite (and perfectly shaded!) pinkish nude lipstick out of her bag and want to ask to use it when she’s done. But the truth is, you just shouldn’t — unless, of course, you have some alcohol-based wipes at the ready to sanitize it. And here’s why: “Even though someone doesn’t have a visible cold sore, they can still carry herpes simplex virus 1 [HSV-1] and pass it off to you in one makeup application,” explains Dendy Engelman, MD, a New York City cosmetic dermatologist.”That’s why it’s so important to reduce the risk of communicating these types of viruses and different types of bacteria to one another by using your own makeup.”
That said, Dr. Engelman broke down which beauty products you should steer clear of sharing and which are safe to borrow from your BFF:
1. Any beauty products that comes in a jar. If you have to dip your fingers into a cleanser, day or night cream, eye creams, foundation, lip balm, etc., it’s best that you (1) wash your hands before coming into contact with the formula and (2) keep that product for your own personal use. “You don’t want to create a petri dish out of the cream you’re going to be applying to your face,” Dr. Engelman says, especially since your body absorbs 60 percent of whatever you apply on your skin (and the bacteria that comes with it).
2. Mascara. Your favorite mascara can harbor bacteria and viruses that are easily transmissible, like conjunctivitis. And since your eyes don’t have the same layers of protection that your skin does, it’s more susceptible to infections like pink eye. “Plus, each time you pull the wand out and push it back in to lube up the brush head, you push air into the dark bottle’s base, feeding the aerobic bacteria that can survive in an oxygenated area,” Dr. Engelman adds. Basically, the only safe way to share your mascara, if you so desire, is to practice what pro makeup artists do and never let the wand that comes with it be used; use only disposable wands to apply it, and never double dip.
3. Pressed foundation. Dry powders don’t hold onto bacteria the way that wet formulas do, but that doesn’t mean you can’t transfer bacteria from one person to another — especially if you’re using a sponge to touch up areas around your mouth or eyes. The only safe way to let your girlfriend use your pressed powder, should she need to touch up her shiny forehead in a selfie emergency, is to spray the powder with an alcohol-based spray, like BeautySoClean Cosmetic Sanitizer Mist, give her a clean makeup brush to use, and have her swipe it over pressed powder once.
4. Lipstick or balm. Lipstick and balms are a hard no to sharing unless you stash an alcohol spray or wipe in your purse to sanitize them. “A large percentage of people carry HSV-1, but just because it’s in your system doesn’t mean you ever show signs of it externally,” Dr. Engelman says. “This is referred to as asymptomatic shedding, where you have the virus but you don’t show any symptoms; it’s all based on your immunity and whether or not something like stress can trigger an outbreak.” That’s why it’s so important to use your own lip products, because if you pass your favorite lipstick around from girl to girl and you or your friend has the virus, you could be transferring bacteria or HSV-1 and never know it. And then you won’t know if you have the capability to develop a cold sore of fever blister until you have it, which is unfortunately too late.
5. Lip gloss. Again, you’re not only pushing air back into the base of your gloss every time you reapply it, but the moist, dark, gummy formula you’re sticking the wand into is the perfect place for bacteria to breed. If it’s your own bacteria, that’s one thing, but you never want to introduce someone else’s bacteria into the formula because HSV-1 and, more frequently, the common cold can spread.
6. Cream shadows. The tacky nature of these types of formulas can trap and harbor bacteria, so it’s best not to pass your cream shadow around to your friends while you guys are getting ready to go out. Especially since you probably use your fingers to apply this type of product and have contaminated it with your own bacteria.
7. Makeup brushes. While acne is an internal skin condition, you can exacerbate the issue by using someone else’s brushes and cross-contaminating bacteria. The only safe way to share your brushes, Dr. Engelman says — and not to sound like a broken record — is to use a fresh brush or spray your used brush with alcohol to kill bacteria. Best practice though, if you are breaking out constantly, is to shampoo them weekly (and then condition them so they last a long time).
8. Toothbrushes. Again, this is a hard no, even though we’ve all been guilty of doing it. “The mouth is filled with bacteria — good and bad. The bad ones are called anaerobic oral bacteria, which are responsible for the smelly volatile sulfur compounds (VSCs) smell if you forget to brush or teeth, or that heighten when you have an infection, Dr. Engelman explains. That’s why it’s so important to (1) brush your teeth regularly (morning and night and after meals if you’re susceptible to cavities) to keep this bacteria at bay and (2) why you shouldn’t be sharing a toothbrush with anyone.
Have a live-in partner and want to share the same electronic toothbrush? Get two different heads to use to keep the bacteria separate.
9. Facial cleansing brush. These devices are under the personal care product category for a reason: They’re not meant to be shared. Think of all the dirt, oil, dead skin cells, and bacteria you clean off your face on a daily basis. Do you want to then buff someone else’s grime into your skin? Nope! Again, if you live with your partner and they constantly steal your facial cleansing brush, like Clarisonic’s Mia Cleansing System, share the unit by buying several brush heads (They’re pretty inexpensive!) so you can have your very own. That, or you can pickup one of these minis for your man from Foreo, so he has his own little facial cleanser.
10. Razors. Razors are important to not share, says Dr. Engelman. Even though stainless steel doesn’t carry bacteria for very long, you can still transfer warts or genital herpes — if you or your friend has either — by someone using your razor or by using someone else’s. Even worse: Razors can nick you and draw blood or fluids, which leave bacteria on the blade after rinsing, making you more vulnerable to a staph infection, hepatitis, or blood-borne viruses (like HIV, although it’s highly unlikely).
Part 2 on what you can share coming in a few days!
This article first appeared on Cosmopolitan.