The objective of the this study was to examine the amount and duration of tea consumption in relation to the risk of renal stone disease.

Previous studies have investigated the association between tea consumption and renal stone disease, but the results are still unclear. Besides, the impact of the duration of tea consumption has not yet been investigated in the aforementioned studies. The present study was conducted as a retrospective research to investigate the relationship between both tea consumption amount and time and renal stone disease. Information on tea consumption was obtained by four closed-ended questions in questionnaires, and the diagnosis of renal stones was established on the results of abdominal sonography.

Inclusion Criteria:

• ≥ 18 years old

Exclusion Criteria:

• individuals with a history of hyperuricemia or gout at baseline, findings of abdominal ultrasound showing transplant kidney, only one kidney, or gouty nephropathy, or missing data

examinees who were ≥ 18 years old and underwent health check-ups with abdominal sonography at the health examination center of National Cheng Kung University Hospital