Fluid intake and all-cause mortality, cardiovascular mortality and kidney function: a population-based longitudinal...

Area of Science:

• Nutrition Science
• Epidemiology
• Nephrology

Background:

• Common advice suggests drinking eight glasses of fluid daily for health benefits.
• However, scientific evidence supporting this recommendation is limited and contradictory.

Purpose of the Study:

• To investigate the relationship between fluid consumption from food and beverages (excluding water) and long-term mortality.
• To examine the association between fluid intake and kidney function, specifically estimated glomerular filtration rate (eGFR).

Main Methods:

• A longitudinal analysis was performed on a prospective, population-based cohort of 3858 Australian adults aged 49+.
• Daily fluid intake was assessed using a food frequency questionnaire, excluding water.
• Multivariable Cox proportional hazard models and bootstrapping were used to analyze mortality and eGFR, respectively.

Main Results:

• Over a median follow-up of 13.1 years, fluid intake was not linked to all-cause or cardiovascular mortality.
• A 250 mL increase in daily fluid intake showed no significant association with mortality.
• Reduced eGFR was observed, but this decline was not associated with fluid intake levels.

Conclusions:

• Fluid consumption from food and beverages, excluding water, does not appear to enhance kidney function.
• This study found no evidence that fluid intake from these sources reduces mortality risk in older adults.