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Almost everyone knows sugar causes decay. Far fewer people know the part that actually determines whether it happens to them.
What happens after you eat
Bacteria in plaque feed on sugar and produce acid. That acid softens the mineral surface of the tooth. Your saliva then spends roughly the next twenty to sixty minutes neutralising the acid and putting minerals back.
Your teeth live inside that cycle all day. Decay happens when the attacks arrive faster than the repair can keep up with them.
Which is why frequency wins
A chocolate bar eaten in one sitting is a single acid attack.
The same bar, in squares, across an afternoon, is six or seven separate attacks — and saliva never gets to finish the repair before the next one starts.
Both halves count. Reduce the total, and reduce the number of separate sugar occasions in a day. Most people already count the total and have never thought about the count.
As a figure to work to: adults and children of eleven and over should keep free sugars under 30 g a day, which is about seven sugar cubes. For children of seven to ten it is 24 g, and for four to six it is 19 g.
The ones people miss
Obvious sweets are rarely the problem, because people already count them. These tend to go unnoticed:
- Tea or coffee with sugar, several times a day
- Fruit juice and smoothies, including those with no added sugar — keep them together to 150 ml a day, with a meal
- Sports and energy drinks sipped slowly through a session
- Dried fruit, which is sticky as well as sugary
- Cough sweets and throat lozenges
- Flavoured water
Anything sipped or grazed slowly is worse than the same thing finished quickly, because it stretches one exposure into many.
Acid without sugar
Sugar-free does not mean harmless. Fizzy drinks, flavoured sparkling waters, citrus and vinegar-based foods are acidic in their own right. They erode enamel directly, without needing bacteria at all.
Diet drinks still cause erosion. They just do not cause decay.
What actually helps
- Keep sugar to mealtimes rather than spread across the day
- Drink water or milk between meals
- Finish a drink rather than nursing it for an hour
- Rinse with water after anything acidic, and keep the acid to mealtimes — that does more than changing when you brush
- Use a fluoride toothpaste, and spit without rinsing
If you want something sweet, having it with a meal is genuinely better for your teeth than having less of it spread through the day.
You do not have to give up sugar to protect your teeth. Mostly you have to stop spreading it out.
