Distilled water is formed by heating ordinary water and then condensing it. Water is basically free of minerals and dissolved gases. The tea we drink is alkaline because of its tannin, caffeine and so on. Acidic water contains less minerals, and the PH value is usually less than 6.8, while alkaline water contains more minerals and is weakly alkaline. The PH value of drinking water in China is 6.8 ~ 7.6, and weakly alkaline water is more beneficial to health. MM people often say that drinking at least eight glasses of water a day means that weakly alkaline water is more beneficial to health.