The Effect of Water Carbonation on Orthostatic Tolerance

What this Trial Is About

Researchers are evaluating whether carbonated water can improve orthostatic tolerance in healthy volunteers. Orthostatic tolerance is the ability to maintain stable blood pressure when standing, which can prevent dizziness or fainting. Drinking water is known to help raise blood pressure and reduce fainting, but it is unclear if carbonation adds any extra effect. The study aims to clarify if carbonated water increases sympathetic nervous activity and blood pressure more than non-carbonated water, which could benefit people with syncope. Participants will undergo a "tilt test" on three separate days to measure their cardiovascular reflexes and orthostatic tolerance, defined as the time until near fainting. On each test day, participants will drink one of three types of water: 50mL still water (control), 500mL still water, or 500mL carbonated water. The order of water types is randomized and single-blinded, meaning the investigator stopping the test does not know which water was consumed, though participants can tell if the water is carbonated. During the study, participants will be monitored for their blood pressure response and time to presyncope during the tilt test. Researchers will assess whether carbonated water improves orthostatic tolerance more than still water. The trial includes multiple visits spaced on separate days, and participants will be asked to drink the assigned water immediately before each test. The primary outcome is the duration of orthostatic tolerance measured in minutes up to 50 minutes.

The Effect of Water Carbonation on Orthostatic Tolerance