Study on How Drinking Water and Non-Sugar Drinks Affect Hydration, Heart Health, and Blood Sugar in Adults Aged 20 to 65

What this Trial Is About

Cardiovascular diseases are a leading cause of death worldwide, with increasing concerns about metabolic dysfunction and type 2 diabetes. Research suggests that the hormone arginine vasopressin AVP, which regulates body fluid balance, may be linked to diabetes risk when water intake is low. This study aims to explore whether increasing water intake with plain water or non-sugar-sweetened beverages can improve hydration, glucose regulation, and cardiovascular health in normal-weight and obese adults. The study involves two groups of adults classified by body mass index BMI as normal weight or obese. Participants will follow an 8-week crossover design with periods of habitual fluid intake, low, moderate, and adequate fluid intake using either plain water or non-sugar-sweetened beverages. Fluid intake is controlled by providing drinks and smart water bottles that record intake and send reminders. The study includes a washout period and weekly lab visits for assessments. Participants will attend weekly lab visits after fasting for at least 10 hours. Assessments include hydration biomarkers from urine samples, body composition, blood pressure, cognitive tests, resting metabolic rate, endothelial function via ultrasound, and oral glucose tolerance tests with multiple blood draws. Continuous glucose monitoring will occur throughout the intervention. Mood, sleep quality, diet, and physical activity will also be monitored using questionnaires and wearable devices. The studys main outcomes include measures of vascular function and glucose regulation over the 8 weeks.

Adequate Hydration and Health Outcomes