Healthy teeth

As the saying goes: "You are what we eat" and when it comes to looking after your teeth this couldn’t be truer. Taking care of your general health by eating a healthy, balanced diet is considered essential for keeping teeth healthy.

Of course, committing to good dental hygiene and making regular trips to the dentist are also important for healthy teeth, but many people forget that one of the biggest causes of tooth decay is consuming too much sugar and drinking acidic and sugary drinks. 

On this page we will explore healthy teeth in more depth, looking into how certain lifestyle habits and foods can help to prevent tooth decay and ensure optimum oral health. 

Tooth decay 

Tooth decay is a widespread problem that occurs when acids in the mouth dissolve the outer layers of teeth. Although cases of tooth decay have decreased over the last few decades, it is still one of the most prevalent health problems in the UK. 

According to the NHS, in England around one in every three adults have tooth decay, while recent research from Public Health England (PHE) has found that one in every eight children aged three or under has decaying teeth.

Symptoms of tooth decay only tend to show as the problem develops. In the advanced stages, symptoms typically include: 

  • Toothache - the pain can start suddenly and may vary from mild discomfort to severe throbbing.
  • Tooth sensitivity - tenderness or pain occurs when eating or drinking something hot, cold or sweet.
  • Grey, black or brown spots appearing on teeth.
  • Bad breath.
  • An unpleasant taste in the mouth. 

If left untreated, tooth decay can lead to further complications such as cavities (holes in the teeth), dental abscesses (pus collecting around the teeth or in the gums) or gum disease. It is important that you make an appointment with a dentist straight away if you are concerned about your teeth. Ignoring the problem could make it worse. 

How does tooth decay develop? 

Tooth decay is a result of the build up of plaque, which attaches to teeth and gradually breaks down the outer layer (the 'enamel'). Plaque is formed of saliva and small food particles. When you consume foods and drinks high in sugar, the bacteria in plaque turns this sugar into energy, producing acid at the same time. If plaque is not removed via the regular cleaning of teeth, plaque can build up and will start to break down the enamel.   

Plaque attached to teeth will start softening and weakening the enamel by drawing out minerals. Over time this leads to the formation of small holes in the teeth (cavities), which cause toothache. The formation of these cavities means the dentine (the softer, bone-like material under the surface of the tooth) becomes exposed to plaque and bacteria in the mouth. As dentine is softer than the enamel, at this stage the speed and severity of tooth decay increases. 

If appropriate treatment is not sought, bacteria and plaque will eventually reach the pulp (the soft centre of teeth that contains the blood vessels and nerves). When the nerves of your teeth become exposed to bacteria, teeth become very painful. If tissue within the pulp becomes infected, dental abscesses may start to form. 

Causes of tooth decay 

There tends to be several factors that contribute to the build up of plaque and the subsequent tooth decay that can develop if proper dental hygiene is neglected. Causes of tooth decay include: 

Poor diet 

Regularly consuming food and drinks high in sugar can increase your risk of tooth decay. These include: 

  • Sweets, chocolate, cakes and biscuits.
  • Buns, pastries, and fruit pies.
  • Ice cream and sorbets.
  • Dried fruit or fruit in syrup.
  • Syrups or sweet sauces.
  • Jams, marmalades and honey.
  • Fruit juice.
  • Sugary drinks including milky drinks with added sugar, energy drinks and soft drinks.
  • Sugary breakfast cereals. 

Drinking alcohol regularly can also lead to tooth decay because the acid contributes to the erosion of the enamel. 


If you smoke, your chances of developing tooth decay are higher than those who don’t. This is because tobacco can interfere with the production of saliva, which helps to neutralise the acids formed in the mouth. 

Dry mouth 

Low levels of saliva can contribute to tooth decay and unfortunately some people naturally have lower levels in their mouth. Alternatively, some medicines and types of medical treatment can lower the amount of saliva, such as radiotherapy and antihistamines. 

Preventing tooth decay 

Maintaining good oral hygiene is key to keeping teeth healthy and preventing tooth decay. The NHS recommends brushing your teeth for at least two minutes, two to three times a day to prevent the build up of plaque. You should also make sure you change your toothbrush regularly and leave at least an hour after eating before you clean your teeth to give saliva in your mouth enough time to neutralise the acids. 

Flossing is particularly beneficial as it helps to remove plaque and food particles that get caught between your teeth and under the gum line. You should try to floss at least once a day. Your dentist can advise you on the best techniques to manouvre the floss through the gaps in your teeth. 

Making simple changes to your diet can also help with preventing tooth decay, and seeing a dietitian or nutritionist will allow you to identify the best foods for healthy teeth and how to incorporate these into your diet. 

Foods for healthy teeth  

In order to reduce the risk of plaque building up and leading to tooth decay, it is recommended that you eat a healthy balanced diet and keep sugar and alcohol to a minimum. Limiting certain types of foods such as citrus fruits and juices can also help to keep teeth healthy. See below for a guide on eating for healthy teeth: 

Watch your citrus intake 

Citrus fruits and juices are a good source of nutrients in moderation, but high consumption can lead to erosion of the enamel. This is because citrus foods and drinks are highly acidic. If you choose to drink fruit juice, only do so while eating or after a meal as your saliva will be able to protect your teeth from the acid. You could also try drinking juice through a straw to prevent the juice from coming into too much contact with your teeth.   

It is also worth noting that a glass of apple of orange juice, depending on its size, contains around four to five teaspoons of sugar, so watching how much you drink is important for overall health as well as healthy teeth. 

Cut down on tea and coffee 

Over time coffee and tea can stain your teeth, and these stains are more persistent than tobacco stains. Studies have also shown that coffee-stained teeth are more resistant to brushing and flossing, and the stains tend to be sticky. As a result they attract food particles and bacteria. Water may have less flavour but it is the best thing you can drink for healthy teeth. This is because it contains fluoride - a mineral that protects against erosion. Aim for six to eight glasses a day. 

Chew gum 

Chewing sugar-free gum after eating can help prevent tooth decay because it encourages the production of saliva, which neutralises the acid in your mouth before it can cause too much damage to your teeth. In addition, many varieties of chewing gum contain xylitol - a type of sugar alcohol that reduces bacteria. 

Eat plenty of dairy

Dairy products such as milk, yoghurt and cheese are rich sources of calcium, which is essential for healthy teeth. Although teeth are not technically bone, they share some of the same properties, so respond well to the strengthening effects of calcium. Healthy dairy choices include low-fat milk and natural yoghurt and small portions of strongly flavoured cheese.  

High fibre foods  

High fibre foods such as leafy vegetables and wholegrain breads, rice, pasta and cereals require a lot of chewing so can help to generate lots of saliva in the mouth. These foods will also physically scrub the teeth in the chewing process, which helps to remove plaque and naturally have low sugar content. 

Further help

Content reviewed by registered nutritionist, Melody Mackeown. All content displayed on Nutritionist Resource is provided for general information purposes only, and should not be treated as a substitute for advice given by your GP or any other healthcare professional. 

The views expressed in this article are those of the author. All articles published on Nutritionist Resource are reviewed by our editorial team.

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