In the classic Chinese novel 'Dream of the Red Chamber', rinsing the mouth with tea after meals is a signature habit of the Jia family. Dental experts point out that this ancient practice contains great wisdom. Regularly rinsing with tea can effectively prevent dental caries, and its efficacy surpasses that of plain water.

Using the first infusion of tea for rinsing offers two key benefits:

First, rinsing can promptly flush out residues from the mouth and between teeth;

Second, tea leaves contain high levels of fluoride, effectively preventing cavities.

Acids from sweets can demineralize tooth surfaces, increasing the risk of caries. Fluoride promotes tooth remineralization, making fluoride-rich tea more effective than water. Additionally, tea polyphenols have strong free-radical-scavenging properties and inhibit cavity-causing bacteria like Streptococcus mutans.

The fluoride content in tea increases with leaf age, with spring-harvested teas having the lowest levels. Brick tea and border tea contain very high fluoride levels; after steeping in boiling water, their fluoride content can instantly reach 100 times that of other teas. It is recommended to use 'aged tea' for rinsing to prevent caries, but consumption of 'aged tea' should be moderated.