Should you brush your teeth before or after breakfast?
While you might think there is a correct answer, the expert advice is mixed.
"There is no uniform guidance from professional organisations on the timing of brushing," explains Santosh Kumar Tadakamadla, professor and discipline lead of dentistry and oral health at La Trobe University.
That means we often rely on what our parents did, or what best suits our morning routine.
"In some cultures, people prefer to brush before breakfast, while in others, brushing after breakfast is preferred," Professor Tadakamadla says.
But there are some key things to know that can help you decide what will be best for your dental health.
What you say
We asked our Instagram audience and of 2519 votes, 75 per cent said you brush after breakfast.
Reasons include "that's how I was taught by mum", "bad breath in the AM", "to remove food particles" and "so breakfast doesn't taste minty".
The 25 per cent who brush before sharing reasons including "I read somewhere it's better to brush first thing", "have brekky at work" and "so I don't swallow the gunk from overnight".
Mixed evidence
It's possible you've received conflicting advice from dentists over the years about when to brush.
"Some resources from the American Dental Association [for example] recommend brushing immediately after waking up so it becomes a part of the routine that cannot be forgotten," says Professor Tadakamadla.
"It also helps flush off the harmful bacteria from teeth, increases saliva flow and forms a protective fluoride layer on the teeth."
However, he says several agencies in Australia recommend brushing after breakfast.
"Brushing teeth after breakfast … offers benefits similar to … [brushing] before breakfast."
But the bonus is, that protective effect lasts for longer.
Arosha Weerakoon owns a dental practice and works as a senior lecturer at the University of Queensland.
She agrees there are pros and cons to both approaches.
How to know what is best for you
Both Professor Tadakamadla and Dr Weerakoon generally recommend their patients brush after breakfast.
"When someone eats after brushing, the saliva could become acidic, and the food particles that remain in the oral cavity also promote the growth of bacteria," Professor Tadakamadla says.
"When someone brushes after breakfast, that challenge is avoided, so the effect of brushing stays a bit longer."
He says people brushing beforehand should at least rinse with plain water after eating.
While it won't dislodge plaque, Professor Tadakamadla says it will help neutralise salivary pH and help remove food substances which contribute to the growth of harmful bacteria.
Dr Weerakoon says she can see why some people prefer to brush first thing in the morning.
"People think 'My mouth is dirty when I wake up, I have bad breath, it's gross', so they want to get rid of that, and that's fine," Dr Weerakoon says.
"But it's like if you've woken up and made your bed, and then 20 minutes later you go back to sleep — it just doesn't seem to make sense."
However, Professor Tadakamadla says "brushing after breakfast might not be recommendable to everyone".
"For those who consume highly acidic foods for breakfast," a fruit smoothie, for example, "brushing immediately after breakfast can cause more harm than good as it could aggravate tooth enamel wear."
But this can be avoided by waiting at least 15 minutes after eating before cleaning your teeth, says Dr Weerakoon.
For those who eat breakfast on the go, she recommends keeping a toothbrush and paste at work, if possible.
How often should we brush?
We should be brushing our teeth twice a day, says Professor Tadakamadla.
"A prime reason for recommending twice-a-day toothbrushing is to deliver fluoride in the toothpaste to the teeth, which plays an important role in preventing tooth decay."
He says the general guidance is to brush for at least two minutes at least twice a day.
The most important clean of the day is before bed, says Dr Weerakoon.
"When we go to sleep, our main protective system, which is our saliva shuts down, which is why we wake up with dry mouth.
"If you go to bed with food particles stuck between teeth, and saliva which is your protective system stops working, then you are more likely to develop holes."
Can you brush too much?
All this talk of bacteria and plaque might have you wondering if it's helpful to brush more frequently than twice a day.
But unless you're at high risk of tooth decay, Professor Tadakamadla says it may cause more harm than good.
Dr Weerakoon says plaque takes time to grow in between cleans, and people risk damaging the tooth surface by brushing too frequently.
Common brushing mistakes
The most common mistake people make is using a toothbrush with hard bristles, Professor Tadakamadla says, adding that soft-bristled brushes are recommend to avoid tooth wear and protect gums.
He says people should also avoid rinsing after brushing, as they are washing way the fluoride that is delivered to the mouth.
A lot of the above advice will come down to the individual, our experts warn.
"Be mindful we are all different. Ask your dentist or your hygienist how you can do better," Dr Weerakoon says.
"We all get excited when our patients ask that."
This is general information only. For personal advice, you should see a qualified medical practitioner.
