Toothbrushes are supposed to keep our little whites clean and yet are themselves full of germs: even those that antibiotics cannot do anything against. You should exchange them accordingly often.
- Fee Anabelle Riebeling
Lots of bacteria cavort on toothbrushes.
According to a US study, there are also many antibiotic-resistant germs among them.
Surprisingly, they found the most resistant germs in people who used mouthwashes and dental floss.
Brushing your teeth twice a day, always from red to white, that’s something dentists tell children about. How often you should replace the brush is not an issue. A study by researchers from the USA now shows: probably significantly more often than we have been doing up to now. You should definitely not wait until it becomes unsightly or starts to smell.
The reason for this is not the large number of germs that the researchers found. It has long been known that the amount is comparable to that on towels or washcloths. Rather, the proven germ mix is unsavory. Ryan A. Blaustein’s team from Northwestern University in the state of Illinois came across not only typical oral bacteria, but also gut bacteria (see box) and germs that are resistant to antibiotics.
The bacteria mix on toothbrushes shows where it is stored. So if there are a lot of intestines on it, the brush is stored near the toilet. When the toilet is flushed, a spray cloud forms which rises into the room. In addition to the water, this can also contain intestinal germs, which are distributed through the air in the bathroom and land on the toothbrush.
The refore, the latter should never be stored near the toilet. If it is not possible otherwise, you should make sure to close the toilet lid before flushing.
Toothbrushes are extreme places
A worrying find and a “milestone in toothbrush research”, explains Markus Egert, Professor of Microbiology at Furtwangen University, in an interview with Spiegel.de. Because responsible for the antibiotic resistance are “certain proteins that destroy the antibiotic or push it out of the bacterial cell.” And Blaustein and his team found 176 different types of them. That is a lot.
But the expert is not really surprised by the find: From a microbiological point of view, toothbrushes are extreme places. “Antimicrobial ingredients from toothpaste and mouthwash and the constant change between wet and dry mean enormous stress for most microbes.” Accordingly, only the toughest would survive there.
An old friend could be responsible
The scientists found most traces of antibiotic resistance on the toothbrushes of people who regularly floss and mouthwash, as they write in the journal “Microbiome”. According to Dirk Bockmühl, a microbiologist at the Rhein-Waal University of Applied Sciences, this could be due to an ingredient often used in such products in the USA: triclosan.
The biocide, which has come under increasing criticism in recent years, is also found in soaps, deodorants and oral hygiene products such as toothpastes or rinses, which, according to Deutschlandfunk Nova, Bockmühl believes is “not a good idea” because it contains antibiotics. Grow resistances. Because of this danger from triclosan and the additional health hazard it poses, a total of 206 researchers and doctors and nine European health organizations called for the substance to be banned in 2017.
At least every three months
The best way to do this is to store it upright in a toothbrush cup. To avoid passing cold viruses from one toothbrush to another, they should be positioned so that they don’t touch.
But no matter how carefully you treat the toothbrush: It must be replaced after three months at the latest, because the bristles lose their flexibility over time and become deformed. If this is the case, they no longer manage to penetrate the small nooks and crannies on the gumline and the spaces between the teeth. In addition, studies have shown that the toothbrushes remove plaque much worse than their new counterparts after three months.
The brushes only have to be changed more frequently if you have been sick before, otherwise the germs in the bristles will cause another outbreak.
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