Modernindividuals frequently experience tooth sensitivity, and the phrase "fearof cold, heat, acid, and sweetness" has become a common term used intoothpaste advertisements to depict this issue. In fact, our ancestors hadalready solved this problem with walnuts.

Walnutkernels have a certain hardness, and strong chewing during consumption not onlyexercises oral function, but also stimulates saliva secretion, improves oralself-cleaning ability, reduces the number of cariogenic bacteria in the mouth,reduces the acidity of acidic substances produced by dental plaque, and thusreduces the probability of dental caries.