Dentist TikToker blows minds after revealing common mistake: 'Stop doing it'

Dr Anna Peterson, a London-based dentist has blown the minds of her TikTok followers after sharing a common mistake people make after brushing their teeth.

In the video, which has been viewed almost 3 million times, Dr Peterson tells her followers, "Using mouthwash after brushing your teeth is going to give you tooth decay."

A dentist has taken to TikTok to share a common dental hygiene mistake that many of us are making when we brush our teeth. Photo: TikTok/@annapetersondental
A dentist has taken to TikTok to share a common dental hygiene mistake that many of us are making when we brush our teeth. Photo: TikTok/@annapetersondental

Unsurprisingly, many of her followers were shocked over the claim as most people tend to use mouthwash straight after brushing their teeth.

"Then what are we supposed to do?!" one user wrote.


In a follow-up video, Dr Peterson explained further, saying, "OK, so if you saw my last video about why you shouldn't use mouthwash after brushing your teeth and you want an explanation, here it is. Your toothpaste that you brush your teeth with has around 1450ppm [parts per million] fluoride, your mouthwash has only 220ppm.

"This is a much lower concentration and it's not enough to protect your teeth from sugars that you eat and drink. So when you brush your teeth and you rinse with mouthwash straight away, you just rinse off all the high concentration fluoride, for a low concentration fluoride."

In response to one viewer saying they've never had a problem with their teeth in 30 years despite using mouthwash second, Dr Peterson's response was that they likely had a good diet, which makes a huge difference.

In another video, she responded to someone who wrote, "What? Everyone rinses with water after brushing. Who is leaving toothpaste on their teeth?"

"No you don't, all you're meant to do is spit out the excess toothpaste, don't rinse it out with water," the dentist responded.

In yet another video, Dr Peterson responded to a question asking when you should actually use mouthwash and she said, "Mouthwash is a fantastic product to use, but you have to use it at the right time of day.

"So you'll wake up in the morning, you'll floss your teeth, brush your teeth and then you'll go and have breakfast. And pretty much anything you're going to eat will contain sugars of some sort and what happens when you eat sugars is that your mouth becomes acidic, so it drops in pH.

"And it drops below 5.5 pH, which is the critical pH and we call this an acid attack. During an acid attack, your teeth start to dissolve, now if you were to go and brush your teeth at this point what's happening is you're brushing the acid into your tooth and this causes tooth erosion. So, to get your teeth out of this critical zone, use mouthwash."

"Soooo unbeknownst to me I've been TRYING to destroy my teeth for decades. Cool," one user commented.

"Wow... mind blowing!! I honestly didn't know this. Thank you for the info," another wrote.

Dr Peterson further blew minds in another video telling her followers to floss before brushing, despite many people saying they'd always done the opposite.

Another video sees the dentist telling people to use a straw to drink coffee to keep your teeth white!

Does anyone else feel like they've been taking care of their teeth the wrong way all these years?

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