Sometimes it seems like there are people who, no matter what they eat, just don’t get cavities. The rest of us are always jealous of these special few. After all, studies show that the vast majority of Americans dread getting cavities.

Here is the main reason why some people just don’t get cavities: it’s in their DNA! Let’s break it down further:

Bacteria

The infectious disease known as dental caries affects 97% of humans. This is what causes cavities. By lowering your mouth’s pH level, the bacteria demineralize the teeth, eroding the enamel protection. But for some lucky people, the teeth can be remineralized by the nutrients found in saliva to stop cavities.

Morphology

Everyone’s teeth are shaped differently. They have natural grooves and ridges in different places. The more grooves and ridges, the more likely bacteria can find their way into these small spaces and cause cavities. The smoother your teeth, the less likely you’ll be plagued by cavities.

Saliva

Everyone’s saliva is composed of different amount of minerals, like calcium and phosphate. These minerals, along with water and fluoride, help protect the enamel on our teeth from harmful bacteria. Some people have a higher composition of certain minerals, which can give them an advantage in fighting cavities.

We can’t all belong to this lucky group. But that’s ok—there are things you can do to drastically reduce your chance of getting a cavity. While you certainly cannot control your DNA, there are many things you can control.

Oral Hygiene

Everyone knows that brushing and flossing is important to a healthy smile, and of course that is true. People who get fewer cavities tend to have very good oral hygiene. But brushing and flossing alone is not enough to prevent cavities.

Diet

Cavities are caused when bacteria breaks down sugar and seeps into tiny holes in our teeth. The general wisdom is that if you cut off the sugar, you cut off the cavities. Of course, this is easier said than done. But pursuing a diet with less sugar will only help your dental health. And remember, avoiding sugar doesn’t just mean candy and other sweets. Fruit juice also contains large amounts of sugar. Try limiting your sugar intake, especially while snacking (when you’re not necessarily going to brush afterward). People with lower cavity counts often limit sugar in a big way.

Sealants

Another step you can take to emulate those people who never get cavities is to consider sealants for “high-risk” teeth. Sealants are a layer on the tooth that covers any holes or cracks, meaning there is no fissure for bacteria to live in. Some lucky individuals naturally have fewer grooves in their teeth, which gives bacteria fewer places to hide. For the rest of us, there are sealants.