Due to its caffeine content - does Red Bull cause dehydration?
Red Bull Energy Drink does not lead to dehydration. This was confirmed by the European Food Safety Authority (EFSA) in their scientific opinion of 2009. It contains the same amount of caffeine as one normal cup of coffee (80 mg / 8.4 fl oz); no other Red Bull ingredient has a dehydrating effect.
However, Red Bull Energy Drink is a functional beverage and not a sports drink. It has not been formulated to deliver re-hydration. Therefore, enough water should be consumed during intense exercise.