Cavities: A Controversial Debate:
Teeth Disease or Nutritional Problem?
© 2018 Health Realizations, Inc. Update
Dental cavities are the most common disease in childhood and the most common chronic disease around the world. Since the 1930s and ‘40s, scientists have been exploring whether there is a genetic predisposition to cavities, or if diet and nutrition are to blame. Unfortunately, there is no absolute answer. Both genetics and nutrition play a role in a person’s predisposition to cavities; however, there is plenty you can do to limit tooth decay and cavities.
What Are Cavities?
Cavities, called dental caries by dental health professionals, are areas on the tooth where the enamel has been eaten away by acid. Cavities can occur anywhere on the surface of a tooth, but can continue to deepen beyond the surface and eat into the entire tooth structure. When they are small or surface cavities, treatment is managed with fillings. If cavities reach the root structure of the tooth, a root canal and crown will typically be required. Therefore, cavities are not just bad for your teeth; they can be expensive and cause multiple, inconvenient trips to the dentist to treat them. Further, the bacteria from your mouth can travel into your bloodstream and impact other areas of your body, an occurrence that is linked to heart disease, diabetes and more.
What Causes Cavities?
Though some debate exists as to what makes people more likely to develop cavities, there is no question as to the mechanism that creates cavities.
Bacteria exist everywhere in your body, including your mouth. A variety of bacteria live in your mouth and on your teeth. When food enters your mouth, it comes into contact with these bacteria. The bacteria feed on the sugar in your food, creating a yellow film called plaque. You have likely seen plaque, but you can also feel it on your teeth. It makes them feel 'fuzzy' or 'filmy.' The more sugar you eat, the more fuel you are giving to the bacteria, and the more they can colonize on your teeth.
Over time, some of the bacteria in these colonies will convert the sugar and carbohydrate in the food and drinks that pass through your mouth into acids. Those acids then dissolve minerals on the surface of your teeth, eroding the enamel. These pits or holes in the enamel can be too small to see with the naked eye, but over time they will grow.
Once the decay passes through the enamel, it enters the main tooth structure, called the dentin. This softer material is even more susceptible to decay and can deteriorate quickly. If decay continues, it can enter the innermost root structure area, called the pulp, and expose the nerve fibers inside the tooth. Though cavities can be painful before reaching this point, once the nerve is exposed the cavity is both more painful and more expensive and invasive to treat.
Propensity for Cavities – Nutrition or Genetics?
Debate rages amongst healthcare professionals about the underlying causes of cavities. While it is true that eating a high-sugar diet means you put more sugar in your mouth for the plaque-causing bacteria to feed on, nutrition isn't the only factor, and its involvement isn't only as direct as the foods that pass through your mouth touching your teeth. The level of overall nutrition in your diet can have an impact as well.
But, diet isn't the only cause of cavities, professionals argue. Those who believe genetics is more of a factor point to the fact that there are people who eat lots of sugar, don't take care of their teeth, and yet never get cavities, while others will eat low-sugar diets and brush after every meal and yet get cavity after cavity.
Studies have shown that there is no simple answer to whether nutrition or genetics cause cavities; the truth is more complex than that. Besides these two factors, additional factors such as personal behavior regarding oral hygiene, environmental issues, and other health conditions can all play into whether or not someone is prone to cavities.
Cavities as Genetic Tooth Disease
A scholarly review of scientific studies on the genetic factors influencing tooth decay found that there is some basis for considering cavities a byproduct of genetic issues; in fact, genetics are proven to be directly or indirectly responsible for between 40-60% of the cavities that a person will develop in their lifetime. This can manifest in several different ways:
Saliva - the composition of a person's saliva is determined in part by genetics and how a person' body digests the food they eat. Some people have more acid-neutralizing components in their saliva than others. These people's saliva will better protect their teeth from decay than someone with less acid-neutralizing components.
Tooth structure - the shape of a person's teeth and how they are positioned in the mouth, determined largely by genetics, is also a major factor on the likelihood of tooth decay. People whose teeth are naturally close together, have cracks or fissures, or are aligned in a way that their teeth cause grooves in each other are all at higher risk for cavities. This is because there are more hiding places for bacteria to gather and it is harder to thoroughly clean teeth with these features. The longer bacteria remains on a tooth, the more damage it can do.
Taste preferences - one study showed that a genetic predisposition to preferring certain tastes will impact a person's chances of getting cavities. For example, a person whose tastes are genetically prone to sweets or carbohydrates is more likely to eat more of those foods, adding to the likelihood that the bacteria on their teeth will have the sugar needed to grow and multiply.
Factors not completely understood - in one study on twins raised separately, despite the difference in their environments, diets, hygiene practices and levels of dental care, identical twins showed similar levels and types of cavities. Researchers continue to examine what other genetic factors might be at work in cases like these.
Predisposition to oral diseases - in addition to a genetic connection to cavities specifically, research shows a connection between family history and the tendency of people to develop other oral diseases such as gingivitis and peiodontitis.
Cavities and Poor Dental Health as Nutritional Degradations
That said, cavities are also strongly linked to the level of nutrition in a person;s diet. There are both direct links, such as that eating more sugar puts more sugar in the mouth for bacteria to feed on, and indirect, more insidious, links, such as:
Poor nutrition means the immune system cannot fight off diseases effectively in the body - including in the mouth. Bacteria are not as effectively eliminated in the mouth of a person whose diet is not balanced, leading to more cavities.
Water is an essential aspect of good nutrition and diet. If you do not get enough water, you will be dehydrated, leading to a drop in saliva production. With less saliva, your teeth lose an important part of their protection against decay.
Lack of calcium can lead to weak structures in your teeth and in the bones in your jaw. Weaker teeth will be more prone to attack from bacteria and weaker bone can cause teeth to shift, misalign, or even fall out.
A lack of vitamin C will cause you to get bleeding, swollen gums, which can trap bacteria against your teeth.
Importance of Good Dental Health and Hygiene Poor dental health has been shown to have a connection with other health issues like heart disease, diabetes, and infections. It is not entirely clear why, but the belief is that the bacteria in your mouth can enter the bloodstream traveling into other areas of the body and causing disease. So to keep yourself at your highest possible level of health, good dental health is important. For optimal dental health, you need to follow both nutrition and hygiene tips:
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