Is Sharing a Toothbrush Really That Gross?

Admittedly, using an instrument that dislodges someone else’s plaque, tartar, and food sounds disgusting–but is using a partner’s toothbrush really that bad? Aside from the ick factor, is using another person’s toothbrush more likely to make you sick, than say, kissing?

Here’s what an expert says:

The reason for sharing a toothbrush is gross

Swapping saliva during a makeout session is very different than using another person’s toothbrush, says Dr. John Grbic, DMD at Columbia University.

“When you brush your teeth you’re actually disrupting the bacteria,” he tells Men’s Health. “Studies show that 100 million bacteria will stick to the toothbrush.”

There’s a good chance that someone will share their plaque or bacteria from periodontal diseases when you use their toothbrush.

But sharing a toothbrush doesn’t mean you’ll get sick

It’s possible, but unlikely, you’ll contract a periodontal disease like gingivitis from the toothbrush of someone who has it, says Grbic.

Bacteria might be transferred into your mouth, but there’s a good chance the organisms won’t like your particular mouth. Without a hospitable environment, the bacteria won’t grow and form a colony. Plus, many kinds of toothpaste include sodium lauryl sulfate, which kills bacteria to further decrease the risk.

However, your risk of contracting a viral infection, such as herpes or Epstein-Barr, which causes mono, is higher, says Grbic. But these can also be picked up through kissing.

The safe way to share a toothbrush

Of course, it’s always best to use your own toothbrush, but what if you’re on vacation without that trusty Oral-B? Grbic says you can safely share a toothbrush by cleaning it first.

“Swirl it in Listerine,” he advises. Alternatively, you can use peroxide if you don’t have mouthwash–just be sure to clean it for at least 15 to 30 seconds.