When staying at a new friend’s house this summer, I noticed that he had a whole drawer full of new, unopened toothbrushes. This struck me as odd at the time, since most sleepovers I was used to did not procure fresh toothbrushes for their guests. Furthermore, I knew couples who share toothbrushes, and did not seem to bother them in the least. As I contemplated which colour I was going to use on my gums from my friend’s drawer, however, the full implication about sharing oral hygiene tools with others hit me. I don’t even share makeup brushes with others, and my eyelashes are not teeming with bacteria and old bits of food like my mouth. I began to wonder- what are the risks of sharing toothbrushes with others? And has awareness of them lead to a buy-new-toothbrushes for guests trend?

There are those who follow the logic of “If I swap spit with someone, then it is the same thing as sharing a toothbrush with them” –not so! Not only are you introducing tons of foreign bacteria into your mouth and leaving your own for the other person, but brushing can sometimes cause the gums to bleed. This is more dangerous than it sounds, since sharing a toothbrush with someone in this circumstance also opens you and them up to various bloodstream diseases, such as hepatitis. Meanwhile, the everlasting adage, “cooties aren’t contagious” has proven not to be as true as we first thought. Cavities are caused by a contagious bacteria– this just gave a whole new meaning to sharing with a friend or loved one.

So, what is the golden rule for brushing your teeth? For one, use a brush with soft bristles to avoid scraping your gums and nicking them, especially now that you know what this can potentially expose you to. Brush twice daily and floss, too! Brushing after breakfast helps rid your mouth of the leftover bits of food that may start decaying in your mouth after a few hours, causing you to have bad breath– even if you’ve just brushed your teeth. Sterilize your toothbrush– use hot, even boiling water to kill off all the bacteria teeming on there. Change your toothbrush at least as often as you change your dates– just kidding– but seriously, around every three months. Toothbrushes get old and tired fast. And of course, as you may have guessed, the most important piece of advice– do not share your toothbrush with others. Sure, you may share jello and yogurt and saliva—oh my!– but that does not mean you should be sharing your instrument of teeth-cleaning.

As I plucked a yellow toothbrush from its nice, clean packaging, I considered waking him to thank him for his thoughtfulness and smart oral hygiene tactics. But as I scrubbed my teeth with a brand-new brush, I decided to return the favour and let him sleep just a few minutes more.