Adequate Hydration and Health Outcomes

NCT07179107 | Recruiting DMC

• 1 other identifier: FP00043890
• Study Type: interventional
• Target: 144
• Locations: 1 country
• Sites: 2

Brief Summary

Cardiovascular diseases (CVD) are the leading cause of death in middle- and high-income countries, according to data from the World Health Organization (WHO). Epidemiological studies have associated low water intake and underhydration with diabetes, chronic kidney disease, and an increased risk of CVD. Similarly, the prevalence of chronic metabolic dysfunction is increasing dramatically worldwide, becoming both a significant public health concern and a global economic burden. Reports from the WHO indicate that the number of people with diabetes worldwide has risen from 108 million in 1980 to 422 million in 2014, representing 8.5% of adults. Therefore, there is an urgent need to identify modifiable risk factors that could help prevent metabolic dysfunction and mitigate the epidemic of type 2 diabetes (T2D). Evidence suggests that the hormone arginine vasopressin (AVP) may play a key role. AVP is the primary hormone responsible for regulating body fluid balance; however, increased AVP secretion, such as under conditions of low water intake, appears to be a risk factor for developing diabetes. Increasing water intake may represent a simple and cost-effective way to improve glucose regulation and cardiovascular health. However, many individuals do not prefer drinking plain water, and although beverages with high sugar content may promote greater fluid intake, they also contribute additional calories that can negatively impact body weight and overall health. Thus, the central research question of this study is whether improving hydration with non-sugar-sweetened beverages can provide equivalent benefits for hydration and health outcomes in adults. Aim 1: To explore the association between habitual fluid intake and fluid preferences (water and non-sugar-sweetened beverages), hydration biomarkers, and health outcomes in normal-weight and obese adults. Aim 2: To compare the impact of increased total water intake, provided as plain water or non-sugar-sweetened beverages, on hydration, cardiovascular health, and glucose regulation in normal-weight and obese adults.

Conditions

Dehydration; Dehydration (Physiology); Glucose Abnormalities; Cardiovascular

Keywords

hydration; dehydration; underhydration; fluid intake; non caloric sweeteners

Outcome Measures

Primary Outcomes (16)

• Flow-mediated dilation %

  Flow-mediated dilation (FMD) will be assessed as a non-invasive measure of endothelial function using brachial artery ultrasound. A high-resolution ultrasound probe will measure baseline artery diameter, then artery diameter after 5 minutes of forearm cuff occlusion, followed by rapid cuff deflation. FMD% will be calculated as a percent of \[(Maximum Post-Deflation Diameter - Baseline Diameter)/Baseline Diameter\]×100 This outcome provides the percent increase in brachial artery diameter relative to baseline, reflecting endothelium-dependent vasodilation.

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Area under the curve for glucose

  The positive integer of the glucose levels during the 120 minutes post ingestion of 75 g of glucose

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Insulin area under the curve

  The positive integer of the insulin levels during the 120 minutes post ingestion of 75 g of glucose

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• glucagon area under the curve

  The positive integer of the glucagon levels during the 120 minutes post ingestion of 75 g of glucose

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Cortisol area under the curve

  The positive integer of the cortisol levels during the 120 minutes post ingestion of 75 g of glucose

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Mean glucose

  Mean weekly interstitial glucose from the continuous glucose monitor

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Glycemic Variability

  coefficent of variation (%) of weekly interstitial glucose from the continuous glucose monitor

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Serum copeptin

  Serum copeptin/vasopressin at baseline of the oral glucose tolerance test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Plasma Sodium

  Plasma sodium at baseline of the oral glucose tolerance test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Plasma Osmolality

  Plasma osmolality at baseline of the oral glucose tolerance test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Total Water Intake

  Weekly average total water intake from Automated Self-Administered 24-Hour (ASA24®) Dietary Assessment Tool

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Urine volume

  24 hours urine volume the day prior to the oral glucose tolerance test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Urine Osmolality

  Urine Osmolality from a 24 hours urine sample the day prior to the oral glucose tolerance test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Reaction time

  Reaction time assessed via Erikson Flankers Test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Accuracy of cognitive test

  Accuracy on the Erikson Flankers cognitive test

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Homeostasis Model Assessment of Insulin Resistance

  The Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), as described by Matthews et al., is a validated index used to estimate insulin resistance from fasting plasma glucose and insulin concentrations. It is commonly applied in clinical trials as a practical and reliable surrogate measure of insulin sensitivity when clamp techniques are not feasible.

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention based on the baseline (0 minutes) fasting blood sample.

Secondary Outcomes (19)

• Confusion-bewilderment

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Depression-dejection

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Fatigue-inertia

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Vigour-activity

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

• Total mood disturbance

  1, 2, 3, 4, 5, 6, 7, 8 weeks of the intervention

Study Arms (8)

Baseline - week 1

OTHER

Habitual fluid intake during week 1 of the study

Other: Baseline - week 1

Low Water intake - week 2

EXPERIMENTAL

Low water intake as described by the protocol

Other: Low Water Intake - week 2

Moderate water intake - week 3

EXPERIMENTAL

Moderate water intake as described by the protocol

Other: Moderate Water Intake - week 3

Adequate Water intake - Week 4

EXPERIMENTAL

Adequate water intake as described by the protocol

Other: Adequate Water Intake - week 4

Washout period - week 5

OTHER

Habitual fluid intake week

Other: Washout - week 5

Low fluid intake with non caloric sweeteners - Week 6

EXPERIMENTAL

Low fluid intake with non-caloric sweeteners - Week 6

Other: Low fluid intake with non caloric sweeteners - Week 6

Moderate fluid intake with non caloric sweeteners - Week 7

EXPERIMENTAL

Moderate fluid intake with non caloric sweeteners - Week 7

Other: Moderate fluid intake with non caloric sweeteners - Week 7

Adequate fluid intake with non caloric sweeteners - Week 8

EXPERIMENTAL

Adequate fluid intake with non caloric sweeteners - Week 8

Other: Adequate fluid intake with non caloric sweeteners - Week 8

Interventions

Low Water Intake - week 2 OTHER

Low water intake as described by the protocol

Low Water intake - week 2

Washout - week 5 OTHER

Washout - week 5

Washout period - week 5

Moderate Water Intake - week 3 OTHER

Moderate Water Intake - Week 3

Moderate water intake - week 3

Adequate Water Intake - week 4 OTHER

Adequate Water Intake - week 4

Adequate Water intake - Week 4

Low fluid intake with non caloric sweeteners - Week 6 OTHER

Low fluid intake with non caloric sweeteners - Week 6

Low fluid intake with non caloric sweeteners - Week 6

Moderate fluid intake with non caloric sweeteners - Week 7 OTHER

Moderate fluid intake with non caloric sweeteners - Week 7

Moderate fluid intake with non caloric sweeteners - Week 7

Adequate fluid intake with non caloric sweeteners - Week 8 OTHER

Adequate fluid intake with non caloric sweeteners - Week 8

Adequate fluid intake with non caloric sweeteners - Week 8

Baseline - week 1 OTHER

Habitual fluid intake during week 1

Baseline - week 1

Eligibility Criteria

• Age: 20 Years - 65 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• BMI 18.5-24.9 or 30.0-39.9 kg/m2
• HbA1c ≤7%
• Age 20-65 y
• available for 8 consecutive weeks same day and time

You may not qualify if:

• Diabetes
• HbA1c \>7% BMI ≤18.5, BMI of 25 to \<30, or ≥ 40 kg/m2
• night shifting work
• losing or gaining weight during the last 2 months (\>5 lbs. fluctuation)
• thyroid medication
• bariatric surgery
• Habitual strenuous exercise (\>120 min/week) Strenuous exercise is defined as activities that take hard physical effort and make you breathe much harder than normal.
• Construction and other workers that spend signifant portion of their work day outdoors
• Commuting by bicycle
• Eating disorders
• Use of aspirin during the duration of the study
• Cancer
• Renal disease (including kidney stones or recurrent urinary track infections
• Hepatic disease
• Cardiac conditions

Sponsors & Collaborators

• Arizona State University: lead

Study Sites (2)

850 PBC

Phoenix, Arizona, 85004, United States

RECRUITING

850 Phoenix Bioscience Core

Phoenix, Arizona, 85004, United States

NOT YET RECRUITING

MeSH Terms

Conditions

Dehydration

Condition Hierarchy (Ancestors)

Water-Electrolyte Imbalance; Metabolic Diseases; Nutritional and Metabolic Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Central Study Contacts

Holly Emmanuel

CONTACT

602-935-7138; hydrate.study@gmail.com

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: OTHER
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Model Details: This is a randomized control trial. Data collection will cover a period of 3 years. Each participant will be part of the study for 8 weeks. Each testing day, once a week will last 3.5 hours. First subject in September 2025 and last subject out July 2028

Study Record Dates

• First Submitted: September 4, 2025
• First Posted: September 17, 2025
• Study Start: September 29, 2025
• Primary Completion (Estimated): July 2, 2028
• Study Completion (Estimated): December 31, 2028
• Last Updated: January 27, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (2)