This is normal, there is no need to deliberately correct. Normal urine pH fluctuations, PH4.8--PH8.0, it is affected by the type of diet, exercise, hunger, taking drugs and disease types. Generally more acidic urine, because the kidneys have acid and alkali retention function. A common cause of urine alkaline: consumed large amounts of vegetables and fruits; the cystitis or pyelonephritis due to decomposition of urea bacteria; mixed with a lot of blood and pus in the urine when the matter; the digestion after a meal climax, dilatation of the stomach and vomiting caused by excessive gastric acid discharge; and the loss of renal tubule when alkali. Uric acid is a common cause of acid: the general reason for the urine are acidic; strenuous exercise, sweating after the protein decomposition in vivo when strong (hunger); pathological causes, such as nephritis, diabetes, acidosis, etc..