CAFFEINATED DRINKS CAUSE DEHYDRATION
The hydrationist, Professor Armstrong from the University of Connecticut, talks about whether caffeinated drinks cause dehydration.
"It’s interesting that in the 1930’s there was a small study done on medical students that showed that when they consumed caffeinated drinks, their output of urine for a few hours increased. However, the researchers in that study did not investigate total body water and did not look at markers of hydration status. So, to counter that study, about eight years ago university students were studied in our laboratory in the United States. We looked at the question of what would happen if 500 mg of caffeine were consumed each day, or about half of that amount, roughly 250 mg. Or if 0 mg of caffeine were consumed each day. And indeed we found by looking at over 20 biomarkers of hydration state, that they were not dehydrated. This explains why we don’t see millions of people in emergency rooms of hospitals who are dehydrated because they consumed caffeinated beverages. So in my opinion, it is a myth that caffeinated drinks cause dehydration."