The pH of urine can normally vary between 4.6 and 6.
Urine pH 1
Urine pH can be affected by various factors after collection such as leaving the urine standing in an uncovered container. Bacteria usually increase the pH as they break down urea in the urine to ammonia.
A diet high in citrus, vegetables, or dairy can increase urine pH (more basic)[dubious – discuss].
A diet high in meat can decrease urine pH (more acidic).
Some drugs also can increase urine pH, including acetazolamide, potassium citrate, and sodium bicarbonate.
Cranberries, popularly thought to decrease the pH of urine, have actually been shown not to acidify urine. Drugs that can decrease urine pH include ammonium chloride, chlorothiazide diuretics, and methenamine mandelate.
Urine pH Hypothyroidism
Role of the diurnal variation of urinary pH and urinary calcium in urolithiasis: a study in outpatients. 2001
We examined the urinary excretion of calcium, oxalate, uric acid, phosphate and magnesium in 96 male outpatients and 142 male inpatients. We also studied the relationship between the stone composition and the diurnal variation of urinary pH in 32 male outpatients (five uric acid stones (UA), 13 pure calcium oxalate stones (CaOX) and 14 mixed calcium oxalate and calcium phosphate stones (CaOX-CaP)) and 53 male inpatients (nine UA, 15 CaOX and 29 CaOX-CaP).
There was a significant difference in the urinary excretion of calcium among outpatients with UA, CaOX and CaOX-CaP (133 +/- 96 vs 219 +/- 97 vs 268 +/- 102 mg per day, P < 0.05). In outpatients with UA, urinary pH was constantly low throughout the entire day. In contrast, outpatients with CaOX and those with CaOX-CaP had diurnal variation of urinary pH that was low in the early morning, followed by elevation in the daytime and was lowered in the night. The pHs in the early morning, afternoon and night were significantly higher in outpatients with CaOX-CaP than in those with CaOX.