Not sure to what extent regular tea can affect the kidneys. But I do know that any kind of ice tea mix, including bottled kind, is bad for the kidneys because it contains high concentrations of oxalate, one of the key chemicals that lead to the formation of kidney stones. Colas are also bad for kidneys because they contain high levels of phosphoric acid, which has been linked to kidney stones and other renal problems. So drinks lots of plain water and add lemon to spruce it up. Lemon is known to counter-attack kidney stones.
