Maybe you saw the segment  on Oprah a few years back. Or the one  on Mythbusters. If so, you may have been freaked out by the thought of your toothbrush being a festering swamp of fecal matter and bacteria.
But that’s TV. Can you trust it? A new literature review  in Evidence Based Dentistry says yes, your toothbrush could become the next superfund site.
All of the studies examined toothbrush contamination and found significant bacterial retention and survival on toothbrushes after use. A number of decontamination techniques were studied and a range of active agents reduced bacterial load. Closed storage containers generally increased bacterial load or survival times. Toothbrush design was also seen to have varying impact on bacterial load.
What kind of microbes  are we talking about? Staph, strep and lactobacillus are most common, with the latter two playing a big role in tooth decay. Other pathogens, such as E. coli and Prevotella, may be present, as well, along with the fungus Candida.
Some of this is just because our mouths are germy places, crawling with microbes – both helpful and harmful – and these can transfer to a toothbrush where they can survive (and multiply) for up to 6 hours after you brush. They can also transfer from one brush to another if they’re stored close enough together to sometimes touch.
Then there are bathroom conditions. No matter how much you clean (or don’t, for that matter), your privy provides an excellent microbial breeding ground. Moisture, warmth and airflow all play a part.
Yet another culprit is the quiet fella in the corner: your toilet. Considering what goes in it, is there any surprise that bacteria are present? And it likes to share its bounty. Every time you flush with the lid up, the water’s action creates a plume of mist and microbes that are cast into the air and spread out like a mini-mushroom cloud.
BUT I HAVE TO BRUSH! you cry. What do I do?
- Rinse your brush with hot water before and after using it, rubbing the bristles with your thumb.
- Store your toothbrush upright and away from other brushes. Never keep it in a drawer or any closed or sealed container. (As our regular readers know, bacteria thrive in dark, closed and damp spaces.)
- Replace your brush frequently. The typical recommendation is every 3 months, but you should swap for a new one as soon as the bristles start looking haggard. (For diligent brushers, this can mean once a month!)
- Close the toilet lid before flushing the toilet. Always.
- Consider sterilizing your toothbrush every so often. There are plenty of ways to do it safely – and without plunking down $30 for a UV light disinfecting gizmo. Some freeze or boil their brush before use. Others run it through their dishwasher or soak it in denture cleaner, antimicrobial rinse or a baking soda/vinegar solution.
That said, disinfecting your brush helps your peace of mind than your health. We’re constantly exposed to all sorts of pathogens  every day just by breathing (more than a few hundred thousand viruses each minute). Your natural defense systems, guided by the biological terrain, are more than sufficient to deal with the vast majority of harmful microbes your toothbrush exposes you to.
That, however, doesn’t make for very interesting TV.