Kuding tea contains more caffeine and theophylline, and excessive drinking of Kuding tea will cause certain damage to the kidneys. The specific performance is as follows:

1. Increase the burden on the kidney: Caffeine and theophylline in Ilex kudingcha will increase the excretion burden of the kidney, which will lead to the decrease of glomerular filtration rate and affect renal function.

2. Stimulate the increase of urine volume: Caffeine and theophylline in Kuding tea can stimulate the increase of urine volume and further affect renal function.

3. Induce urinary tract infection: Excessive drinking of kudingcha will concentrate urine and increase the chances of bacterial growth, which will lead to urinary tract infection.

4. Inducing stones: Oxalic acid in Kudingcha is easy to deposit in the kidney or urinary tract to form stones, which in turn leads to kidney diseases.

Therefore, although Kuding tea has a certain health care function, it should be drunk carefully to avoid adverse effects on the kidneys.