Bad Teeth? Don't Blame Your Genes—Blame Yourself

We can blame a lot on our parents—our weird Christmas traditions or inexplicable fear of balloons for instance—but one thing we have to take credit for is our oral health. A new study involving twin siblings has found that there are some aspects of our oral health that are hereditary, but the factors that play a role in our likelihood of developing cavities are all our own.

It's pretty clear by now that there is bacteria everywhere, but when it comes to the human body, the warm, moist mouth is a particular hotspot for these little critters. Recently, researchers from The J. Craig Venter Institute, a nonprofit genomics research center, took a closer look at some of the bacteria that makes a home in our mouths to determine the limits of genetics on oral health.

"What we are seeing here is that in general you do indeed inherit the microbes that make up your mouth from your parents," Dr. Chris Dupont, one of the researchers involved with the study, told Newsweek. "But it turned out that the microbes you inherit from your parents don't generally cause cavities. Instead, it's more due to what you eat, your lifestyle and your diet."

For the study, the team looked at twins, both fraternal and identical, to better understand the role that genetics play in our oral health. The team also specifically looked at twins from the ages of 5 to 11, because they hypothesized that younger children would have an oral microbiome that more closely resembled the one they were born with than adults. In addition, younger twins are more likely to share the same environment than older twins.

Cavities are formed when bacteria in the mouth convert sugar to acidic plaque that eats away at the tooth. Therefore, the type of bacteria in your mouth plays a major role in how likely you are to get cavities. However, the study results emphasized that we do not inherit these cavity-forming bacteria from mom and dad, but rather pick them up through our own poor lifestyle choices.

In addition to uncovering the origin of mouth bacteria, the study found that the amount of hereditary bacteria in our mouth diminishes over time. The findings are novel, as it's the first time that researchers have actually sequenced the bacteria inside our mouths. They traced both where they come from, and what they do or don't do.

"I think this actually emphasizes what we already believe, that it's your habit and lifestyle that influence cavities, and that it's important to brush your teeth and limit sugar intake," said Dupont.

And what are inherited bacteria responsible for? It's still a mystery, but the J. Craig Venter Institute plans follow-up studies to find out exactly how much mom and dad are to blame.