can ice tea cause dehydration?
A: If the iced tea is decaf it should be a lot less dehydrating than tea with caffeine. It's the caffeine in tea (and coffee) that accounts for the majority of the diuretic effect those brews have. There are other substances in iced tea that are slightky diuretic, but the caffeine is the main culprit.
This new study adds to the evidence, that among everyday coffee drinkers â say, those of us who routinely sip a cup of Joe or two at the office â the old wives' tale that coffee will lead to dehydration is really just that: a tale.