To keep body healthy it is necessary to maintain the right acid-alkaline balance, which is generally referred to as pH balance.
What is pH
According to Britannica encyclopedia, pH is a “quantitative measure of the acidity or basicity of aqueous or other liquid solutions”. Generally speaking, it reflects the concentration of hydrogen ions in liquid solution. Pure distilled water has pH = 7 that means that a solution is neutral (acid ions are equal to alkaline ions). If pH less than 7, a solution is acidic (the less the number, the more acidic environment). Consequently, if pH more than 7, it means that a solution is alkaline (the more the number, the more alkaline environment)