20 Things You Should Never, Ever Share

20. Tweezers

At your friend’s house and spot a stray eyebrow hair? It may be tempting to borrow her tweezers, but here’s why you really shouldn’t. As Mount Sinai Medical Center’s Joshua Zeichner told Allure in 2015, “If any bleeding occurs as the hair is pulled from the follicle, it can contaminate the tweezers and infect someone else who uses them.”