The effect of caffeinated, non-caffeinated, caloric and non-caloric beverages on hydration.

Objective: To examine the effect of various combinations of beverages on hydration status in healthy free-living adult males.

Methods: In a counterbalanced, crossover manner, 18 healthy adult males ages 24 to 39, on four separate occasions, consumed water or water plus varying combinations of beverages. Clinical guidelines were used to determine the fluid allowance for each subject.