Author: Dr Alexandra Jones, Co-Founder and Board Chair
When we think about food and our health, we usually think about what happens after we swallow it.
Food enters our digestive system, where it’s broken down, nutrients are absorbed, and our bodies use them to keep us alive and healthy. We understand, at least broadly, that food is metabolised.
But there’s another part of the story that’s particularly important for oral health. Before food reaches your gut, it spends time in your mouth. And while it’s there, it can act directly on the surfaces of your teeth and the environment around them.
Imagine drinking a soft drink. Once you swallow it, the ingredients in that drink enter your digestive system and are eventually absorbed and metabolised by your body. But that’s not the first interaction. The drink has already washed across your teeth, gums and other surfaces in your mouth.
Its sugars may be used by bacteria living in dental plaque, which can produce acids. If the drink itself is acidic, that acid can also come into direct contact with the surface of the teeth.
So the same thing we eat or drink can affect us in different ways:
- systemically, through what happens once it is digested and metabolised
- topically, through what happens when it comes into direct contact with the mouth
That second part is often overlooked, so in this post we’re aiming to shed some light!
Throughout the day, minerals can move out of and back into the surface of our teeth. Saliva plays an important protective role, helping neutralise acids, wash substances away and support the recovery of tooth surfaces.
This is one reason oral health isn’t simply about whether a particular food is “good” or “bad”.
How often we eat or drink something, how long it stays in contact with our teeth, what else we consume, and how much recovery time our mouth gets can all matter.
For example, slowly sipping an acidic or sugary drink over several hours creates a very different pattern of exposure from having that same drink with a meal.
Likewise, frequently grazing throughout the day can mean the mouth has fewer opportunities to recover from acidic conditions and return to a healthier balance.
This is why FRED’s approach to preventive oral health looks at factors such as free sugars, food timing, snacking patterns, acidic drinks, hydration and saliva together, rather than treating diet as a single question about what someone eats.
We often think about sugar when it comes to our nutrition and teeth, but the acidity of food and drinks is something we don’t hear a lot about.
Acid can gradually dissolve minerals from the surface of our teeth, causing a loss of tooth structure through a process known as dental erosion. This can happen even when tooth decay is otherwise well controlled.
Other sources of acid can come from inside the body, including conditions that cause stomach acid to regularly enter the mouth.
Again, what matters isn’t only what we consume. Frequency, timing and the length of time teeth are exposed all influence what happens at their surface.
The good news is that simple strategies can help, and even if you just try one, you’ll likely notice the difference within just a few days of giving it a go.
Of course, what and when we eat isn’t always entirely within our control. Cost, convenience, work schedules and other circumstances all influence our life. That’s why it’s worth focusing on small, achievable changes – like the tips below:
- Keep acidic and sugary foods and drinks around mealtimes where possible, rather than sipping or grazing on them frequently throughout the day.
- Avoid habits that prolong contact with your teeth, such as slowly sipping, swishing or holding drinks in your mouth.
- Drink water after eating or drinking, particularly after something acidic, to help clear the mouth and support saliva.
- Give your mouth a break between meals and snacks, allowing saliva time to help the environment in your mouth recover.
- Support your saliva, including by staying hydrated. Sugar-free chewing gum can also help stimulate saliva after eating or drinking.
- Wait before brushing after something acidic. Acid temporarily softens the tooth surface, so rinsing with water and waiting around 30-60 minutes before brushing can help protect it.
- Pair acidic foods with other foods where it makes sense. For example, having fruit as part of a meal rather than grazing on it over a long period reduces the number of separate acid exposures.
- Choose foods and drinks that can help the mouth recover. Milk and cheese, for example, can help to balance the effects of the acids, while plain water is a good everyday drink.
An important part of looking after our mouths is understanding how food interacts with our teeth, the role saliva plays in protecting them, and how small everyday habits can help.
Got questions for the FRED team, or want to know more about the science behind oral health? We’d love to hear from you!
Drop us a line at hello@fred.org.au