Carbonated drinks contain a lot of food additives. Some carbonated drinks can cause serious damage to human cells. If carbonated drinks contain preservative sodium benzoate, it will destroy an important area of human mitochondrial DNA. Except that sugar can replenish energy for human body, aerated "carbonated drinks" contain almost no nutrients.

Lactic acid bacteria (LAB) are a kind of bacteria that produce a large amount of lactic acid by using fermentable carbohydrates. This kind of bacteria is widely distributed in nature with rich species diversity, including at least 18 genera and more than 200 species. Except for a few, most of them are indispensable flora with important physiological functions in the human body, which widely exists in the human intestine.