What and how we choose to eat and drink, as well as toothbrushing and flossing influence the risk of developing tooth decay. Understanding, preventing and managing tooth decay is more complex than just sugar. Our teeth are important. Adults usually have 28 in total.

Teeth have three layers:

Enamel - the hard, mineralised outside layer

Dentine -  a partly porous connective tissue 

Pulp -  the soft centre with blood vessels and nerves

Tooth decay happens when your teeth are coated in plaque that contains bacteria. This bacteria  makes acids from fermentable carbohydrates, including starch and sugars. If this occurs repeatedly over a period of time, cavities or holes will form and eventually an infection if they are not treated. Below is some advice from dental associations on the factors that cause dental decay as well as how to protect your teeth.

Types of food

All fermentable carbohydrates, including sugars and starches, can cause bacteria to grow on teeth. Foods that stick to teeth, or sit in the mouth for longer increase the risk.

Some carbohydrate foods are also protective as they contain milk proteins, calcium and phosphates. They can help reduce the risk but don't remove it. 

Eating habits

How often you eat may be more important than the actual amount that you eat. This is because constant snacking or sipping upsets the natural protective mechanisms in the mouth and there is more frequent contact between carbohydrates, plaque and teeth.

Try to keep sugary foods and drinks to mealtimes - The advice is to 'give teeth a rest' between meals and snacks for around 2 hours, so the natural effect of acids and saliva can take place to help protect teeth. Saliva washes foods away from teeth, and neutralises acids, but also re-mineralises teeth and repairs minor damage caused by plaque acids.

Chewing sugar-free gums can stimulate saliva production, and the sugar-alcohol based products like xylitol can also help to protect teeth.

Sharing food and drinks can transfer plaque bacteria especially in infants and toddlers. Parents should take care when children’s teeth are erupting to not share spoons and toothbrushes.

Professional Advice

Oral hygiene routines are important- regular brushing with fluoride toothpaste and flossing removes plaque.

Visit a dentist regularly for a check up and to get preventive treatment. Dentists can advise about other factors that increase risk of dental decay, including many medications.

Fluorides

Dentists recommend people of all ages use fluoride toothpaste when brushing teeth. Fluoride slows down the softening of dental enamel by acid and speeds up the rehardening by saliva.

Water fluoridation can be a cost-effective, equitable and safe means to help protect against tooth decay.

REFERENCES

• van Loveren C. (2018). Sugar Restriction for Caries Prevention: Amount and Frequency. Which Is More Important? Caries Research, 53(2):168-175.
• Anderson CA, Curzon MEJ, Van Loveren C, Tatsi C, et al. (2009). Sucrose and dental caries: a review of the evidence. Obes Rev, 10 Suppl 1:41-54.
• Australian Dental Association. Factsheet. Diet and oral health. How eating and drinking habits affect our teeth. Accessed 17 July 2020 https://www.ada.org.au/Your-Dental-Health/Resources-for-Professionals  
• New Zealand Dental Association. Tooth decay. Accessed 17 July 2020 https://www.nzda.org.nz/public/your-oral-health/tooth-decay