This statement is unscientific, and medical people suggest that cleaning tea dirt is good for health.
Tea scale is harmful to health.
If the tea set is used frequently, it is not washed often. Over time, a layer of brown tea dirt will form on the surface of the teapot, which is harmful to human body.
-Tea leaves contain tea polyphenols, which are easily oxidized to form tea scale when contacted with air and water, and attach to the surface of teapots and teacups, especially rough pottery. Harmful substances such as arsenic, mercury, cadmium and lead in tea scale will hinder the absorption and digestion of nutrients in the small intestine, causing inflammation and even necrosis of organs such as kidney, liver and stomach. Therefore, always clean the tea set. If the tea has tea dirt, it can be scrubbed with toothpaste, detergent, etc. Its descaling effect is very good.