What Causes Cavities?

Caries, or tooth decay, is a preventable disease. Most caries are mild, but they may negatively impact your quality of life. Although not as common, extremely severe, untreated caries can have significant health consequences.

What causes cavities, simplified:

  • Bacteria eat sugar.
  • Bacteria create acid.
  • Acid weakens enamel.
  • After 20 minutes, saliva neutralizes acid (usually).
  • During that 20-minute period, cavities are being formed.

Sugars right before bedtime skip the saliva step, and create acid for hours while sleeping, creating cavities during the entire night. (This is why brushing at night time is the most important!) Even natural sugars from milk or juice can cause cavities.

Frequent snacking or sipping during the day can cause severe decay as well. As an example, one glass of milk with lunch won't cause cavities, but the exact same glass of milk sipped on every 30 minutes all day for weeks on end will cause many cavities very quickly. Avoid constant grazing or sipping behaviors to avoid the most severe decay patterns. Click here to learn more about preventing cavities.