Holding urine for a long time will cause certain hazards to the human body: 1. Holding urine for a long time, the bladder is in a state of high pressure, which may cause urine reflux in the bladder, ureter and kidney, that is, urine in the bladder retrograde into the kidney and ureter, causing hydronephrosis or kidney infection, which may cause kidney function damage or kidney failure over time; 2. Holding urine for a long time can cause the bladder forceps muscle Compensatory thickening, when the bladder can be formed in the small room trabecular changes, over time it is easy to cause fatigue of the bladder forced urinary muscle, and lead to bladder forced urinary muscle does not work, does not contract or forced urinary muscle fibrosis, etc., and lead to poor bladder elasticity, urinary difficulties, upper urinary tract water, etc.; 3, long time holding urine, urine can produce a concentrated state, can form bladder infection or bladder stones and other hazards.