How often should I replace my toothbrush? A dentist weighs in

When's the last time you replaced your toothbrush? For many people, the answer is "too long ago."

"The average person should be swapping out for a new toothbrush every three to four months," Dr. Kevin Sands, a dentist based in Beverly Hills, told CBS News. "This ensures that the bristles are still effective and bacteria accumulation on the toothbrush is minimal."

The American Dental Association says you should also replace your toothbrush more often if the bristles are visibly matted or frayed.

With virus season upon us, it's a good reminder to take any recent sickness into account — this expedites when you should make a swap. This includes being sick with anything from COVID to the flu, a common cold or strep throat.

"After you've recovered from being sick, it's best to start off with a new toothbrush that is clean and fresh, just to be safe," Sands says. "It's an easy fix for lingering bacteria."

(The ADA notes that while toothbrushes have been shown to harbor bacteria, "there is no evidence that these bacteria cause adverse health effects.")  

Toothbrush hygiene tips

So how do you keep your toothbrush in the best condition until it's time to replace it? Sands and the ADA suggest giving it a rinse after each use.

"For most people, using hot running water to rinse your toothbrush is usually enough to keep it clean on a daily basis," Sands says. "Hot water will help soften the bristles and release toothpaste and food particles." 

Practicing proper storage is also key. "Bacteria can easily grow on toothbrushes, so it's important to store them in a clean, dry place," Sands says.

That means no toothbrush caps or covers, which can trap microbes on your bristles. 

"Microbes love to grow in moist and dark places, and that's the toothbrush when you cover it up," California-based dentist Dr. Kami Hoss told CBS News Sacramento earlier this year.

A protective case in your suitcase or toiletry bag is a good way to keep your toothbrush clean while traveling, Sands adds, but remember to take it out of the case and allow it to air dry between uses.

If you share a bathroom with someone, the Centers for Disease Control and Prevention also suggests avoiding contact between brushes to prevent bacteria from spreading.

"If more than one brush is stored in the same holder, do not let them touch each other," the CDC advises.