Chewing gum is a snack food that adults and children like very much. Chewing gum can not only drive away drowsiness, but also make a lot of saliva in the mouth to maintain oral health. What exactly is xylitol chewing gum? Why can chewing xylitol gum keep teeth healthy? In order to answer these questions, let us explore the scientific secrets hidden in xylitol chewing gum.

Xylitol does have the effect of promoting tooth recalcification and preventing tooth decay. But before introducing the principle of this effect, let us first understand the structure of teeth and the state in the oral cavity, and how tooth decay is caused. Our teeth are composed of enamel, dentin, and cementum from the outside to the inside. Among them, tooth enamel can crush food and protect tooth body. Tooth enamel is the hardest and most delicate tissue in the human body. Then there is the dentin, thin tubes called dentinal tubules that run throughout the dentin, from the pulp to the interface with the enamel, where the dental nerve runs. Finally there is cementum, which has bone-like properties and connects the teeth to the frontal bone. Because of the saliva in our mouth, it is often kept in a moist state, which also makes a lot of oral bacteria resident in the mouth. While many of these oral bacteria aid in the digestion of food, there are also bacteria that cause tooth decay. The teeth in our mouth are covered with a thin film called pellicle, which is formed by glycoproteins contained in saliva and is only a few microns thick. Some of the bacteria in the oral cavity will attach to this pellicle, absorb nutrients from the sugar in the food, and secrete some sticky substances. One of the representative bacteria is the culprit of tooth decay--Streptococcus Mutans.

The viscous substance secreted by Streptococcus mutans will form tartar. While multiplying in the tartar, they take sugar into the body and decompose it. While obtaining energy, they also produce by-products such as lactic acid. As the life of Streptococcus mutans continues, the acidity of the tartar will continue to increase. As a result, the calcium and phosphoric acid in the not acid-resistant cementum will be dissolved and lost, which is called "decalcification". If you don't remove the tartar, tooth decay will eventually form.

But Streptococcus mutans is not the only bacteria that causes tooth decay in the oral cavity. All bacteria that can ferment sugar and other substances and produce acidic substances are the pathogenic bacteria of tooth decay. For example, bacteria such as lactic acid bacteria in the normal flora in the oral cavity can also produce acidic substances, so they are also harmful to dental health. However, because these bacteria can be easily removed by saliva and brushing, the negative impact on teeth is actually not great. In other words, there are not only harmful bacteria in the mouth that cause tooth decay, but also good bacteria that have little effect on dental health.

Next, let’s talk about xylitol again. Xylitol, which became famous because it is used in chewing gum, is actually a natural sweetener extracted from plants. It is ubiquitous in many kinds of trees, vegetables and fruits. The sweetness of xylitol is the same as that of granulated sugar, but its calorie content is only 75% of that of granulated sugar. It is a low-calorie sweetener, and its safety has been recognized by the Food and Agriculture Organization of the United Nations and the World Health Organization. Moreover, from a structural point of view, xylitol is a five-carbon sugar alcohol, and all sugar alcohols are non-fermentable. The so-called non-fermentable means that they will not be fermented by bacteria in the mouth. In other words, it will not become food for bacteria that cause tooth decay, so even if xylitol is ingested, it will not produce acidic substances.

In addition, xylitol also has a unique property that it can inhibit the growth of harmful bacteria Streptococcus mutans. Because xylitol cannot be digested and absorbed by Streptococcus mutans, when Streptococcus mutans mistake it for food and ingest it into its own cells, it takes a lot of effort to spit it out. And because it has to repeat meaningless huffing and puffing movements desperately, the Streptococcus mutans will become weaker and weaker, and the number will gradually decrease. Not only that, but the most interesting thing is that only the harmful bacteria in Streptococcus mutans that damage teeth can do this meaningless huffing and puffing behavior, while the beneficial bacteria will not do this useless work. In other words, we can reduce harmful bacteria by taking xylitol, and can retain beneficial bacteria with low pathogenicity, thereby reducing the probability of tooth decay. This property is the real main reason that xylitol can be used in chewing gum.

Finally, because xylitol has an endothermic reaction when dissolved in water, after ingesting xylitol, a cooling sensation can be produced in the mouth. Moreover, chewing xylitol gum also helps our body digest, strengthens teeth and gums, and activates the brain. So, let's chew xylitol gum relievedly.