NCT05843318

Brief Summary

This study is a randomized controlled intervention trial in adults aged 50+ years with overweight or obesity, which will compare three groups with different diet prescriptions: 1) pre-meal water consumption (500 ml, before each main meal) with a hypocaloric diet; 2) 1500 ml water consumed throughout the day with a hypocaloric diet; 3) hypocaloric diet with no instructions regarding water consumption. Smart water bottles will objectively assess water intake timing and volume. Urine osmolality, urine volume, and serum osmolality will be used as objective indicators of compliance with the water intake prescription. We will investigate changes in perceived hunger and fullness and appetite-regulating hormones as potential mechanisms by which premeal water could improve appetite regulation. We will also investigate the impact of water consumption and hydration on executive function capabilities, which may influence intervention adherence. Although increasing water intake could be an effective weight management strategy, no evidence-based recommendations exist for the timing of water intake needed for this benefit.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
375

participants targeted

Target at P75+ for not_applicable

Timeline
22mo left

Started Nov 2023

Longer than P75 for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress58%
Nov 2023Mar 2028

First Submitted

Initial submission to the registry

April 12, 2023

Completed
24 days until next milestone

First Posted

Study publicly available on registry

May 6, 2023

Completed
6 months until next milestone

Study Start

First participant enrolled

November 13, 2023

Completed
4.1 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 20, 2027

Expected
3 months until next milestone

Study Completion

Last participant's last visit for all outcomes

March 31, 2028

Last Updated

November 14, 2025

Status Verified

June 1, 2025

Enrollment Period

4.1 years

First QC Date

April 12, 2023

Last Update Submit

November 12, 2025

Conditions

Outcome Measures

Primary Outcomes (1)

  • Body weight change

    Body weight change in weight loss and weight loss maintenance phases

    weeks 0 to 12 in the weight loss phase, month 0 to 12 post weight loss phase

Secondary Outcomes (3)

  • Change in appetite sensations

    weeks 0 to 12 in the weight loss phase, month 0 to 12 post weight loss phase

  • Change in hydration status

    weeks 0 to 12 in the weight loss phase, month 0 to 12 post weight loss phase

  • Change in executive function (EF)

    weeks 0 to 12 in the weight loss phase, month 0 to 12 post weight loss phase

Other Outcomes (1)

  • Changes in appetite hormones

    weeks 0 to 12 in the weight loss phase, month 0 to 12 post weight loss phase

Study Arms (3)

Pre-meal water + Hypocaloric diet

EXPERIMENTAL

premeal water ( 500 ml) before each main meal, three times per day + hypocaloric diet

Behavioral: Water intake and weight control in older adults - Premeal Water + hypocaloric diet

Daily water + Hypocaloric diet

EXPERIMENTAL

total daily water prescription (1500 ml/d) + hypocaloric diet

Behavioral: Water intake and weight control in older adults - Total Daily Water + hypocaloric diet

Hypocaloric Diet alone

ACTIVE COMPARATOR

hypocaloric diet with not instructions regarding water intake

Behavioral: Water Intake and weight control in older adults - hypocaloric diet alone

Interventions

Individuals will be randomly assigned to one of three groups. All individuals will receive counseling in a structured hypocaloric meal plan (1200-1500 kcal) that is consistent with a healthy dietary pattern as described by the Dietary Guidelines for Americans. This group will receive specific instructions for daily water intake timing and volume.

Pre-meal water + Hypocaloric diet

Individuals will be randomly assigned to one of three groups. All individuals will receive counseling in a structured hypocaloric meal plan (1200-1500 kcal) that is consistent with a healthy dietary pattern as described by the Dietary Guidelines for Americans. This group will receive specific instructions for total daily water intake.

Daily water + Hypocaloric diet

Individuals will be randomly assigned to one of three groups. All individuals will receive counseling in a structured hypocaloric meal plan (1200-1500 kcal) that is consistent with a healthy dietary pattern as described by the Dietary Guidelines for Americans. This group will receive instructions in the hypocaloric diet, without specific fluid intake recommendations.

Hypocaloric Diet alone

Eligibility Criteria

Age50 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • aged 50+ years
  • BMI ≥25 kg/m2
  • weight stable (+/- 2 kg) in past 6 months
  • willing to provide consent and comply with study protocol

You may not qualify if:

  • usual plain drinking water intake \>1500 ml/d
  • uncontrolled hypertension (\>159/99 mmHg)
  • medical condition requiring specialized diet prescription (eg, T2D, CHF wih fluid restriction)
  • medical condition that precludes participating in a physical activity program (eg, orthopedic injury)
  • current or history of GI disease (eg, Crohn's), GI surgery, or medications which impact GI function
  • allergies or aversions to foods included in the test meals

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Virginia Tech

Blacksburg, Virginia, 24061, United States

RECRUITING

MeSH Terms

Conditions

OverweightObesity

Interventions

Drinking

Condition Hierarchy (Ancestors)

OvernutritionNutrition DisordersNutritional and Metabolic DiseasesBody WeightSigns and SymptomsPathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

EatingNutritional Physiological PhenomenaDiet, Food, and NutritionPhysiological PhenomenaDigestive System Physiological PhenomenaDigestive System and Oral Physiological Phenomena

Study Officials

  • Brenda Davy, PhD RDN

    Virginia Polytechnic Institute and State University

    PRINCIPAL INVESTIGATOR

Central Study Contacts

Brenda Davy, PhD RDN

CONTACT

Elaina Marinik, PhD

CONTACT

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
TRIPLE
Who Masked
PARTICIPANT, INVESTIGATOR, OUTCOMES ASSESSOR
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
Professor

Study Record Dates

First Submitted

April 12, 2023

First Posted

May 6, 2023

Study Start

November 13, 2023

Primary Completion (Estimated)

December 20, 2027

Study Completion (Estimated)

March 31, 2028

Last Updated

November 14, 2025

Record last verified: 2025-06

Locations