What increases my risk of tooth decay?

A diet high in sugars, poor oral hygiene, a dry mouth, and infrequent visits to the dentist can increase your risk of tooth decay. The bacteria in your mouth called plaque secrete acids which eat into the teeth causing decay. Plaque uses the sugars in your food to make the acid. Limiting sugars and brushing and flossing away the plaque can cut down on tooth decay. A dry mouth helps the plaque to grow. Sipping on water throughout the day can help a dry mouth. Finally, regular visits to the dentist are important to keep the teeth cleaned from plaque and tartar buildup and identify future potential teeth problems. 

Tooth decay is caused by bacteria, so the simplest answer is anything that promotes an environment for the bacteria to thrive. 

The bacteria require sugared foods to live, so they love a diet full of sugar and carbohydrates. Brushing and flossing remove the bacteria from the teeth, so poor oral hygiene allows the bacteria to multiply quickly. Your saliva protects the teeth, so anything that reduces saliva flow such as medications also increases your risk of developing tooth decay.

There are many things that increase the risk of tooth decay. Here are a few:

  • Not brushing or flossing
  • Sugary / sticky foods (which increase bacteria)
  • Dry mouth (decreased saliva means less food particles washed away)
  • Eating disorders (bulimia, etc. - stomach acid isn't good for teeth)
  • Not seeing your dentist

The above are far and away the most causes.


The foundation of good oral health is mostly dependent on personal behaviors. Poor health behaviors at an early age result in a cumulative effect on poor oral health. So it is imperative that new parents provide good nutrition and practice early oral hygiene. Parents should practice good oral hygiene by initially wiping an infants gums before they have teeth with a damp cloth. Once teeth erupt parents should use a damp cloth or gauze to remove plaque from teeth, and subsequently use a toothbrush. Starting at age 2, a fluoride toothpaste should be used, with only a pea sized amount of toothpaste on the brush. As well, parents should be aware that it is not the quantity of sugar children consume that results in more tooth decay, but the frequency of exposure to sugars. So "watering down" juice does not reduce tooth decay risk, and in some cases increases the risk of decay since it increases the time of exposure to consume the juice. Sippy cups that contain juice, even 100% fruit juice, increases time of exposure to sugar and increases risk of tooth decay. As well, putting a child to sleep with a bottle that contains anything other than water can increase risk of tooth decay. Parents who divert from the above ideal practices are more likely to have children that develop tooth decay at an early age.

This question can't be answered fully in the 2500 word limit allotted here! Most of the risk factors are local ones such as diet and hygiene, which many of you may already be familiar with. I will discuss these in a slightly different manner. First of all, if a person loses their ability to keep their mouth wet such as normal aging, the taking of certain medications (for blood pressure as an example), the prolonged use of oxygen, radiation or chemotherapy, then their risk of having tooth decay goes right off the chart! People who suffer from bulimia and addicts usually have high decay rates. The purging that bulimics engage in washes their mouths with extremely caustic stomach acids and destroys massive amounts of tooth structure. Addicts whether alcohol, cocaine, heroin, PCP or any other form of chemical usually have poor nutritional habits and poor hygiene. The intake of highly refined carbohydrate "junk foods" that most addicts subsist on makes their decay rate very high.

The most commonly seen and treacherous cause of tooth decay in my opinion is that of exposures per day. In short, it's not the amount of sugar it's the number of times per day the sugar is in your mouth. Children and infants are constantly snacking and eating. Be sure what they are putting in their mouths is not always a sugar source. Sugar comes in so many forms it would take too long to list them all here. If the food you are eating is processed, if it has a bar code on it, it could easily have added sugar. If the food you eat is identifiable as food as seen in nature, you are safer from added sugar. In between meals eat raw fruit, nuts and the like. Fruit juice and glazed nuts are processed. A granola bar, decay wise is no better than a candy bar!  Finally, drink more water -- plain water -- than you are used to and be sure to rinse your mouth out after snacks, and you can greatly lower your risks of decay.

I've briefly tried to explain to you the many risk factors for tooth decay under your control. You don't have to floss all your teeth, just the ones you want to keep.
Diet is the biggest risk for tooth decay. Sugary foods, sodas, sports drinks, diet sodas (the preservative is phosphoric acid), chewable vitamin C, chewing gum (that has sugar in it, as opposed to sugar free) refined carbohydrates that stick to teeth, frequent snacking between meals -- all increase the risk of decay. Not brushing and flossing your teeth allows the bacteria in the mouth to turn these foods to acid that eats away the enamel (outer layer of the tooth) causing tooth decay.
Poor oral hygiene is the most common risk for tooth decay. Not brushing and flossing properly allows plaque deposit accummulation which lead to acid attack on enamel, resulting in tooth decay. Genetic factors, health conditions and certain medications also increase your risk of risk decay. Seeing a dental professional for biannual check up and cleaning can decrease your risk greatly.
The most common thing that increases the risk of tooth decay is not brushing and flossing your teeth after eating and before bed. The frequency of eating sticky and sugary foods and drinking soda and other acidic drinks can also increase the risk of getting tooth decay. Finally, not seeing you dentist regularly can increase your risk of having tooth decay go untreated and then needing a more advanced procedure like root canal or extraction.
Some factors that may increase a person's risk of developing tooth decay include the following:

  • poor oral hygiene
  • active tooth decay
  • eating disorders
  • drug or alcohol abuse
  • lack of regular professional dental care
  • active orthodontic treatment combined with poor oral hygiene
  • high levels of tooth decay-causing bacteria in the mouth
  • exposed root surfaces of teeth
  • decreased salivary flow, resulting in dry mouth
  • poor diet
  • existing restorations (fillings)
  • tooth enamel defects
  • undergoing head and neck radiation therapy

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.