100% Xylitol All-Natural Dental Defense System May Reduce the Risk of Tooth Decay Non-GMO Gluten-Free Sweetened Only with Xylitol Halal Kosher Spry Dental Defense System Spry - Improving Oral Health Frequent eating of foods high in sugars and starches can promote tooth decay. Clinical studies have shown that the use of xylitol on a daily basis, spread throughout the day, may reduce the risk of tooth decay. Every batch tested in USA to ensure the highest quality.