Even though tooth enamel is stronger than skeletal bones, it may decay as adults age. The January issue of the Mayo Clinic Health Letter examines what causes tooth enamel to wear down and what individuals can do to prevent it.

Experts say too little saliva is a main culprit of early tooth decay. It supplies high levels of calcium and phosphate particles that enhance protection of the tooth’s enamel surface. In addition, saliva protects the mouth by washing away food and the sticky film of acid-producing plaque that can cling to teeth.

Healthcare providers say individuals with chronic dry mouth should be evaluated to find its cause since too little saliva usually results from various health conditions or the medications used to treat them.

Ways to combat too little saliva include treating medical conditions, altering medication dosages or chewing sugar-free gum with xylitol.

Another cause of decaying enamel is too little fluoride. This mineral is important to dental health because it makes teeth stronger and enhances saliva’s remineralizing, anti-decaying properties.

Fluoride is usually obtained through drinking fluoridated water and brushing with fluoride-enhanced toothpastes. Nutritional supplements containing the mineral and fluoride rinses may also help preserve tooth enamel.

Dental experts say to avoid acidic foods known to be detrimental to tooth enamel. These include citrus fruits, tart candies, diet and regular sodas or sports drinks, fruit juices and wine.