Effect Of A Daily Liter Of Water Consumption On Caloric And Fluid Intake

Fluid intake is the most effective, direct strategy to pursue euhydration. Previous studies have inadequately investigated the effect of supplying fluids on Calorie and fluid intake or hydration status. This may indicate an effective intervention for improved hydration or aid in research methods for future study. PURPOSE: Determine whether a six-week water supply changes Calorie and fluid intake or hydration status. METHODS: Thirty participants (21 females; 24.9 6.2y, 167.7 8.3 cm, 75.3 19.2 kg) were provided and asked to consume two 500 mL bottles of water per day for six weeks. No other direction was provided in terms of adding, or replacing supplied fluids to habitual fluid intake. Therefore, our intervention required 1 L of water consumption per day, without changing other daily habit. During three time points (pre-, 3-week, and post-supplement), participants recorded food and fluid intake, and collected all urine for 24-h. Total fluids consumed (TFC) and total caloric intake (TCI) were assessed by 24-h self-reported food and fluid logs (Nutritionist Pro, Attaxya Systems). Hydration status was assessed via 24-h urine specific gravity (USG), urine osmolality (Uosm), and urine volume. Repeated measures ANOVA were run with SPSS (v. 28, IBM) to compare differences in TFC, TFI, and hydration status among pre-, 3-week, and post-supplement. Significance was set α priori at p .05. RESULTS: TFC was not significantly different between time points (pre: 1795 ± 654 mL; 3-week: 2120 ± 856 mL; post: 1956 ± 645 mL; p = .175). TCI was not altered with our supplementation (pre: 2610 ± 2000 kcal; 3-week: 1952 ± 773 kcal; post: 1779 ± 659 kcal; p = .117). USG was also not significantly different between time points (pre: 1.015 ± .007; 3-week: 1.013 ± .006; post: 1.014 ± .005; p = .197). Uosm was significantly increased at our 3-week time point compared to baseline (p = .009), but this increase did not persist (p = .209) at post-supplementation. Total urine volume was not significantly different among time points (pre: 1695 ± 945 mL; 3-week: 1816 ± 906 mL; post: 1617 ± 725 mL; p = .363). CONCLUSION: Simply providing water for consumption may improve hydration within 3-weeks, however, any increases are minimally significant and return to baseline by 6-weeks. Future studies should examine water supply and hydration with a larger sample size.