Hydration and health at ages 40-70 years in Salzburg Austria is associated with a median total water intake over 40 mL/kg including at least 1 L/d plain drinking water.

Introduction: To address longstanding questions about how much plain water to drink for hydration and long-term health, this study described the plain water intake (PWI) of people without chronic health conditions (CHC), at ages 40-70 years, who met hydration criteria (Healthy+Hydrated). Methods: Community-dwelling participants in the population-based Paracelsus 10,000 study in Salzburg, Austria ( Results: For Healthy+Hydrated women, the median PWI and TWI were 1.5 L/d (22 mL/kg) and 2.9 L/d (45 mL/kg), respectively. For Healthy+Hydrated men, the median PWI and TWI were 1.3 L/d (17 mL/kg) and 3.0 L/d (40 mL/kg). None of the Healthy+Hydrated reported zero PWI. In gender-specific Poisson models, the Healthy+Hydrated group had significantly lower relative risk of PWI < 20 mL/kg AND TWI < 45 mL/kg than each of the CHC+Hydrated, Healthy+Not Hydrated, and CHC+Not Hydrated groups. For Healthy+Hydrated participants with >60% of TWI from PWI, PWI ranged between 20 and 45 mL/kg/d. Conclusion: In the Paracelsus 10,000 study population, hydration and health at ages 40-70 years was associated with a median PWI of at least 1 L/d.