
That might not sound like a shocking headline for those of us whom have been taught to brush right after every meal from an early age. But recent reports from the past decade have been suggesting something different.
Articles from the Mayo Clinic, Colgate, and New York Times among others have been advocating waiting 30 to 60 minutes after eating to brush. Apparently the delayed brushing movement has gotten so strong that parents Japan are beginning to complain to schools making children brush their teeth right after lunch time.
So the Japan Society of Pediatric Dentistry (JSPD) issued a statement telling everyone to not believe the hype and that it’s actually in your best interest to brush right away.
■ Research
According to the JSPD this notion came from a study that tested the effects of acidic food on dentin, a substance in our teeth. They didn’t say which study it was specifically, but other reports link back to an experiment conducted by Georg August University in Germany in 2003.
In the study scientists tested samples of dentin that have been submerged in acidic Sprite Light for 90 seconds. They then embedded the samples in people’s mouths and had the subjects brush their teeth at different times from 10 to 60 minutes afterward.
After 21 days of this, the dentin samples of people who brushed their teeth in less than 30 minutes from Sprite contact experienced significant erosion because of the added friction from the brush. Therefore it’s advisable to wait about half an hour after eating to brush, right?
Wrong, according to the JSPD.
■ Reality
This is not to say there’s anything wrong with the Georg August University’s findings. It’s just that it doesn’t really apply to regular life. First, the JSPD points out that the study was testing the effects of acid directly on dentin, which is the middle layer of a person’s tooth and protected by the enamel and saliva.
Of course enamel is not impervious to acid either and the neutralizing effects of saliva are not perfect, but they do act as a sufficient defense against reasonably acidic foods and drinks. So even with the combined effect of scrubbing with a brush you probably won’t get much penetration.
Next, there’s the issue of “erosion” as mentioned in the study. This is different from the type of acid attack that causes cavities. As previously mentioned taking a swig of Sprite will splash a layer of acid onto your pearly-whites but must also contend with your body’s natural defenses. These not only weaken the acid in the food but also help withstand the physical force of brushing.
On the other hand, the plaque that builds up from food particles poses a much greater threat. Plaque contains decaying carbohydrates which in turn contain bacteria that produce acid. This is like having a tiny acid factory in direct contact with your teeth and protected from the outside by plaque.
While both situations are harmful to your teeth, the plaque and its acid-making bacteria are by far the greater threat. Following that logic, the best way to deal with plaque is to brush food matter away as soon as possible after eating. Waiting only gives plaque more opportunity to form.
The JSPD are confident in their advice but also vow to conduct further studies on the matter. In the meantime, they urge everyone young and old, to not hesitate to brush even after consuming acidic drinks or foods.
However, if you have a hard time trusting any of these research institutes, then you can always do what I did and get an entire mouthful of gold teeth implanted. It’s remarkably liberating. Not just with dental hygiene either, my social calendar has been free and clear for months.
Source: Japanese Society of Pediatric Dentistry (Japanese), NCBI, Mayo Clinic, The New York Times, Colgate Oral and Dental Health Resource Center (English)
Top Image: Wikipedia – Certo Xornal (Cropped by RocketNews24)
Inset Images: RocketNews24




Japanese government planning higher ticket prices for foreign tourists at Tokyo National Museum
Starbucks Japan unveils new sakura cherry blossom collection for hanami season 2026
7-Eleven Japan now sells bagels…cooked in bamboo steamers
Visiting Japan’s one-and-only, and only-for-a-limited-time, Dragon Ball noodle restaurant[Photos]
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Japanese government planning higher ticket prices for foreign tourists at Tokyo National Museum
Starbucks Japan unveils new sakura cherry blossom collection for hanami season 2026
7-Eleven Japan now sells bagels…cooked in bamboo steamers
Visiting Japan’s one-and-only, and only-for-a-limited-time, Dragon Ball noodle restaurant[Photos]
Starbucks Japan releases new sakura goods and drinkware for cherry blossom season 2026
Manga is More than Just Reading, It’s a Cultural Experience – Expo 2025 with The Seven Deadly Sins
Starbucks Japan reveals exclusive sakura goods at Reserve Roastery Tokyo
Studio Ghibli now sells Ursula’s backpack from Kiki’s Delivery Service at its anime shop in Japan
One Piece creator has hidden secret of anime treasure’s identity in chest at bottom of real-world ocean
8 sakura sweets to enjoy under the cherry blossoms at your next hanami picnic in Japan
Starbucks Japan releases first-ever Hinamatsuri Girls’ Day Frappuccino
Japanese restaurant chain serves Dragon Ball donuts and Senzu Beans this spring
Is Tokyo Station’s startlingly expensive wagyu bento boxed lunch worth its high price?[Taste test]
Japan’s cherry blossom season predicted to start earlier than we’d thought, especially in Tokyo
Japan Extreme Budget Travel! A trip from Tokyo to Izumo for just 30,000 yen [Part 2]
Japan’s craziest burger chain takes menchi katsu to new extreme levels
Sakura Festival in Chiyoda mixes illuminations, boats, music, and Rilakkuma in the heart of Tokyo
Viral Japanese cheesecake from Osaka has a lesser known rival called Aunt Wanda
Japan’s newest Shinkansen has no seats…or passengers [Video]
Foreigners accounting for over 80 percent of off-course skiers needing rescue in Japan’s Hokkaido
Super-salty pizza sends six kids to the hospital in Japan, linguistics blamed
Starbucks Japan unveils new sakura Frappuccino for cherry blossom season 2026
Foreign tourists in Japan will get free Shinkansen tickets to promote regional tourism
The 10 most annoying things foreign tourists do on Japanese trains, according to locals
Take a trip to Japan’s Dododo Land, the most irritating place on Earth
Naruto and Converse team up for new line of shinobi sneakers[Photos]
Survey asks foreign tourists what bothered them in Japan, more than half gave same answer
Japan’s human washing machines will go on sale to general public, demos to be held in Tokyo
Starbucks Japan releases new drinkware and goods for Valentine’s Day
We deeply regret going into this tunnel on our walk in the mountains of Japan
Studio Ghibli releases Kodama forest spirits from Princess Mononoke to light up your home
Major Japanese hotel chain says reservations via overseas booking sites may not be valid
Put sesame oil in your coffee? Japanese maker says it’s the best way to start your day【Taste test】
No more using real katana for tourism activities, Japan’s National Police Agency says
Manga is More than Just Reading, It’s a Cultural Experience – Expo 2025 with The Seven Deadly Sins
Starbucks Japan reveals exclusive sakura goods at Reserve Roastery Tokyo
Studio Ghibli now sells Ursula’s backpack from Kiki’s Delivery Service at its anime shop in Japan
One Piece creator has hidden secret of anime treasure’s identity in chest at bottom of real-world ocean
8 sakura sweets to enjoy under the cherry blossoms at your next hanami picnic in Japan
Take a trip to Japan’s Dododo Land, the most irritating place on Earth
Tokyo Skytree turns pink for the cherry blossom season
Is Starbucks Japan’s new Hinamatsuri Girls’ Day Frappuccino suitable for adults?
Starbucks Japan reveals new sakura drinkware collection, inspired by evening cherry blossoms
Starbucks Japan reveals first sakura Frappuccino for cherry blossom season 2020
Sakuramochi festival sweetens things up at Tokyo’s Seibu Ikebukuro this season