Here's a link to a story about how drinking large amounts of iced tea could lead to kidney failure.
http://www.msn.com/en-us/health/medical/mans-kidneys-fail-after-drinking-too-much-tea-case-study/ar-AAalwzF?ocid=anshlthreu11 (http://www.msn.com/en-us/health/medical/mans-kidneys-fail-after-drinking-too-much-tea-case-study/ar-AAalwzF?ocid=anshlthreu11)