People who drank water had lower fasting glucose levels and better hydration levels than the control group. But it was slightly easier for the diet beverage group to reduce calories in the short-term, at three months – as compared to the water group. People may do better slowly weaning themselves off caffeine as they transition to water, says Dr. Brie Turner-McGrievy, one of the study’s authors and Assistant Professor in the Department of Health Promotion, Education and Behavior at the University of South Carolina. Dr. Turner-McGrievy and colleagues are exploring how sweet preference plays a role in sticking to beverage substitution over time.If you are swapping beverages straight across, though, it makes sense that you could lose weight.
Since over 20 percent of America's calories come from sugar-sweetened beverages, it makes sense to switch to water or lower calorie drinks.