What Causes Cavities And What Are The Risk Factors?

what causes cavities

Most of us have had to deal with a dental cavity at some point or the other. In fact, the World Health Organization estimates that around 60 to 90% of school children and almost all adults have cavities.1 So why are cavities so common and what causes them?

What Causes Cavities?

Cavities are more likely to develop on the surfaces that you use to bite and the areas between your teeth where food particles tend to lodge.2 Tooth decay may also occur in crevices around fillings where the filling has fractured or weakened.3


Now, we all know that cavities can cause serious problems like pain, tooth loss, tooth abscess, serious infection, and trouble chewing.4 But have you ever wondered what causes cavities in the first place?

Bacteria Removes Minerals From Teeth Enamel

Your mouth contains bacteria which are harmful to your teeth and these tend to form a film known as plaque over your teeth. You may be able to feel this sticky substance if you run your tongue over your teeth before you brush. The tooth surfaces that feel slightly rough and furry rather than smooth are likely to have plaque on them. The bacteria in plaque convert carbohydrates from the food or drinks that you consume into energy for its needs and, in the process, also produces acid. This acid can eat away at the enamel of your teeth in a process known as demineralization.


Saliva, Water, And Toothpaste Replenish These Minerals

But your teeth are not completely defenseless against this acid attack. Minerals like phosphate and calcium present in saliva and fluoride from water or toothpaste can help replace lost minerals and repair your enamel in a process known as remineralization.

Cavities Form When More Minerals Are Lost Than Replaced

Tooth enamel typically gets demineralized and remineralized many times during the day, but some factors can upset this balance. As a result, the rate at which minerals are lost exceeds the rate at which they are replaced. When this happens, over time, the surface of the enamel starts to break down, and a hole or cavity begins to develop.


As the decay progresses, bacteria first breach the enamel and enter the softer layer known as dentin which lies beneath. They then progress to the pulp which contains blood vessels and nerves. At this point, you typically experience pain. Bacteria can also cause an abscess in the pulp and even spread to your bone.5

What Are The Risk Factors For Cavities?

Let’s take a look at some factors that can up your risk for cavities and see if you have these signs and symptoms of cavities.


1. Infection By Oral Pathogens

Adults typically have bacteria that cause tooth decay in their mouths. But according to research, babies are not born with these bacteria. So how do these oral pathogens infect your baby? They’re usually passed on through the saliva of a caregiver, mostly the mother. And this can happen quite early in life before your baby even has her first tooth.

People with cavities have increased levels of cavity-causing bacteria in their mouth and are, therefore, more likely to pass it on. So, getting proper treatment for cavities as well as avoiding sharing things like forks or spoons with your baby can lower the risk of transmission.6


2. Poor Oral Hygiene

As we saw, plaque contains bacteria which release tooth-decaying acid. The lack of an appropriate routine for maintaining oral hygiene can lead to the development of cavities. Brushing twice a day with a fluoride toothpaste and flossing every day can help clear out plaque and keep your teeth clean. Oil pulling with sesame or coconut oil every day can also improve your oral health.

3. Frequent Snacking

Snacking frequently on foods with carbs like sweets, juices, and drinks increases the number of times your teeth come in contact with foods that can be used by bacteria to produce enamel-destroying acids. This means an increase in the frequency of acid attacks on your teeth and a greater chance of tooth decay.7 And it is unlikely that you brush your teeth or rinse your mouth after each snack.


4. Sodas And Sticky, Crunchy, And Sweet Foods

The bacteria in your mouth love sugar. So sweets or other foods high in sugar can be especially bad for your teeth. Sticky foods like dates or toffee which tend to cling to your teeth or crunchy foods like chips which can get lodged between teeth also increase your chances of developing cavities as they remain in contact with your teeth for longer periods.8 Children especially tend to gather cavities through this route.

Soft drinks and sodas also contribute majorly to teeth erosion. Not only do the high-sugar varieties feed teeth-decaying bacteria, the diet sodas also contain high amounts of citric and phosphoric acid which erode the teeth enamel as well as the dentin. Use a straw to minimize exposure.


5. Dry Mouth

Dry mouth is a condition characterized by low levels of saliva in the mouth. Saliva is your natural defense against demineralization. Not only does it neutralize and dilute acids which erode your enamel but it also contains minerals which are used to remineralize your teeth. So low levels of saliva can increase your chances of getting cavities. Medical conditions like Sjögren’s syndrome, diabetes, disorders of the salivary glands, nerve damage, chemotherapy, as well as certain medicines can cause dry mouth.9

6. Smoking And Alcohol Consumption

The use of tobacco can impede the production of saliva while excessive consumption of alcohol can play a part in the erosion of enamel. So avoid smoking and keep your alcohol intake moderate to keep your teeth healthy.10

7. Bulimia

Bulimia is an eating disorder characterized by episodes of binging on food and then purging by vomiting or by using laxatives or enemas. Vomit is acidic in nature, and excessive exposure to it can wear away the enamel of your teeth.11 This can lead to poor oral health and up your risk of cavities.

8. Bottle Feeding With Sugary Drinks

Bottle feeding with sugary drinks can keep your baby’s or toddler’s teeth in contact with sugar for long periods of time. And as we already saw, bacteria use these carbohydrates to produce acid which can cause cavities. Putting your baby to bed with a bottle containing something high in sugar like fruit juices, milk, or formula is a particularly bad idea. In case your baby needs a bottle to go to sleep, give her plain water. Also, do keep in mind that the American Dental Association suggests that children should be persuaded to start using a cup by the age of 1.12 This can help reduce the risk of cavities for your toddler.

How Can You Prevent Cavities?

Follow these tips to treat cavities naturally before it’s too late:

  • Eat more alkaline foods like cruciferous and green leafy vegetables, cayenne peppers, and garlic to compensate for the erosive acidic nature of other foods.
  • Eat more foods rich in calcium and vitamin D to compensate for the teeth mineral loss.
  • Cut back on sweets, candy, fruit juice, soda, and foods with hidden sugars like processed and packaged snacks.
  • Try ayurvedic remedies like mustard, amla, licorice to keep a cavity from getting worse.
  • Try oil pulling to maintain optimum oral hygiene and use fluoride toothpastes.