Recruiting

Snacks & Eating Behaviors

Sponsor:

University of Colorado, Denver

Code:

NCT07428187

Conditions

Overweight/Obesity

Eligibility Criteria

Sex: All

Age: 25 - 45

Healthy Volunteers: Not accepted

Interventions

Snack Type 1: Walnuts

Snack Type 2: Pretzels

Study Details

Brief summary:

This study plans to learn more about how different types of snacks may affect brain processes relating to eating behaviors during a diet intervention.

Conditions

Overweight/Obesity

Study ID

NCT07428187

Start date

Mar 5, 2026

Status verified date

Mar, 2026

Completion date

Mar 31, 2028

Anticipated

Primary completion date

Mar 31, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 25 - 45

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 25-45 years old
  • BMI at least 27 kg/m2
  • Comfortable completing a weight-loss intervention\\
  • Willing to consume a daily snack of either walnuts or pretzels

Exclusion Criteria:

  • Nut or wheat allergy
  • History of bariatric surgery
  • Current eating disorder
  • Current illicit substance use
  • Current pregnancy, lactation (or less than 3 months after stopping lactation), or less than 6 months postpartum
  • Uncontrolled hypertension (>160/100 mmHg)
  • Significant endocrine/metabolic disease kidney disease, liver disease, or blood disease that would be anticipated to affect study results
  • Taking injectable medications, sulfonylureas, or meglitinides for diabetes treatment
  • Taking weight-loss medications, or steroids within \~3 months prior to study participation (e.g., GLP-1 receptor agonists)
  • Significant mental health changes within \~3 months prior to study participation (e.g., medication adjustments, new psychiatric diagnoses, hospitalization relating to mental health concerns)
  • Neurological illnesses or injury that would be anticipated to affect MRI data
  • Weight change greater than 10% within 3 months prior to study participation
  • Currently participating in another weight-loss study
  • Not comfortable eating the study-provided meals (with allowances for dietary preferences) and/or following a highly restrictive diet (e.g., vegan)
  • MRI-specific exclusion criteria (e.g., metal in the body, weight >500 lbs

Study Design

Enrollment

70 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Other

Interventions and Outcome Measures

Arms

experimental: Snack Type 1: Walnuts

Participants will complete a 12 week diet intervention, during which they will be asked to reduce their daily caloric intake. During the diet intervention, participants in the Snack Type 1 group will be asked to eat a daily snack of walnuts, which will be provided by the study team. Participants will meet with study staff on a weekly basis during the intervention (with some meetings virtual and in-person visits every 2-3 weeks).

active comparator: Snack Type 2: Pretzels

Participants will complete a 12 week diet intervention, during which they will be asked to reduce their daily caloric intake. During the diet intervention, participants in the Snack Type 2 group will be asked to eat a daily snack of pretzels, which will be provided by the study team. Participants will meet with study staff on a weekly basis during the intervention (with some meetings virtual and in-person visits every 2-3 weeks).

Interventions

Snack Type 1: Walnuts

Participants will complete a 12 week diet intervention, during which they will be asked to reduce their daily caloric intake. During the diet intervention, participants in the Snack Type 1 group will be asked to eat a daily snack of walnuts, which will be provided by the study team.

Snack Type 2: Pretzels

Participants will complete a 12 week diet intervention, during which they will be asked to reduce their daily caloric intake. During the diet intervention, participants in the Snack Type 2 group will be asked to eat a daily snack of pretzels, which will be provided by the study team.

Primary outcome measure

  • Percent change in Blood Oxygen Level Dependent (BOLD) response to visual food cues as measured by functional magnetic resonance imaging [ Time Frame: Baseline, 12 weeks ]

Central Contacts and Locations

Central contacts

Allison Hild, BS

3037249024allison.hild@cuanschutz.edu

Kristina T Legget, PhD

303-724-5809kristina.legget@cuanschutz.edu

Locations

University of Colorado Anschutz Medical Campus

Recruiting

Aurora, Colorado, United States, 80045

Contacts

Kristina Legget, PhD

303-724-5809kristina.legget@cuanschutz.edu

Allison Hild, BS

303-724-9024allison.hild@cuanschutz.edu

Principal Investigator:

Kristina T Legget, PhD

More Information

Sponsor

University of Colorado, Denver

Last update posted

Mar 23, 2026

Last verified

Mar, 2026

Keywords

  • Dieting
  • Weight loss
  • Overweight
  • Obesity
  • Food
  • Neuroimaging
  • Body weight
  • Eating
  • Brain
  • Magnetic resonance imaging

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by University of Colorado, Denver on 2026-03-23.