Iced tea contains high levels of oxalate, a key chemical that leads to the formation of kidney stones. Dehydration is the most common cause for kidney stones and, when combined with increased iced tea consumption, will raise the risk for the condition. Men are 4 times more likely to develop kidney stones than women, and the risk rises dramatically after age 40.
“For people who have a tendency to form the most common type of kidney stones, iced tea is one of the worst things to drink,” said Dr. John Milner from the Department of Urology at Loyola University Chicago Stritch School of Medicine. “People are told that in the summertime they should drink more fluids. A lot of people choose to drink more iced tea, because it is low in calories and tastes better than water. However, in terms of kidney stones, they might be doing themselves a disservice.”
Though hot tea also contains oxalate, it’s hard to drink enough to cause kidney stones, Dr. Milner explained. About 85% of tea consumed in the United States is iced, according to the Tea Association of the USA.
To quench thirst and properly hydrate, Dr. Milner suggests drinking water. Real natural lemonade is another good option since lemons, being high in citrates, inhibit the growth of kidney stones.
SOURCE: Loyola University Medical Center