Recruiting
Phase 1
Phase 2

Pecans & Pretzels

Sponsor:

Texas Tech University Health Sciences Center

Code:

NCT07348406

Conditions

Cognitive Assessment

Psychological Function

GI Health

Eligibility Criteria

Sex: All

Age: 50+

Healthy Volunteers: Not accepted

Interventions

Pecan snack

Pretzel snack

Study Details

Brief summary:

This project will investigate whether daily snack consumption can improve memory, mood, and overall brain function in people with cognitive impairment. Sixty participants, aged 50 and older, with cognitive impairment, will be randomly assigned to eat snacks, either pecans or pretzels, for three months. Researchers will also study how snacks (pecans and pretzels) may influence the body, including changes in gut bacteria, blood markers of inflammation, and signals that connect the gut and the brain.

Conditions

Cognitive Assessment

Psychological Function

GI Health

Study ID

NCT07348406

Start date

Mar 15, 2026

Status verified date

Sep, 2026

Completion date

Sep 30, 2028

Anticipated

Primary completion date

Sep 30, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 50+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • men and women > 50 years-old
  • self-reported IQCODE (informant questionnaire on cognitive decline in the elderly) average score < 4.5
  • self-reported significant functional impairment (related to cognitive impairment) in basic or advanced activities of daily living as evidenced by the Activities of Daily Living (ADLs) questionnaire. If answers to at least one endorsement in the "NO, dependence due to memory concerns".
  • Stable medications (≥ 12-week unchanged dose before baseline) with no planned changes during trial.
  • habitually consume less than two servings (2 ozs = 1/4 cup) of nuts or nut spreads per week
  • willing to accept randomization

Exclusion Criteria:

  • reported nut allergy or intolerance
  • self-reported untreated hypothyroidism, severe liver disease, or end-stage chronic kidney disease
  • heavy alcohol drinker: in the past 3 months: men ≥14 drinks/week or women ≥7 drinks/week
  • recent (<1 month) appearance of diarrhea or hematochezia before study intervention begins. Rationale: A one-month waiting period after diarrhea or hematochezia (blood in stool) is recommended for a gut microbiome test to ensure the results accurately reflect the state and microbial composition, since diarrhea and hematochezia can significantly alter the gut environment and skew test results.
  • recent (<1 month) exposure to antibiotics before study intervention begins. Rationale: A one-month waiting period after antibiotics is recommended for a gut microbiome test because it allows the microbial community time to recover and reach a more stable state, ensuring a more accurate and representative snapshot of the gut microbiome composition, since antibiotic usage can significantly reduce microbial diversity.
  • Self-reported unstable GI disorder
  • likeliness of moving during the trial, lack of transportation, or unavailability at sample collection times

Study Design

Enrollment

60 participants

Anticipated

Allocation

Randomized

Intervention Model

Parallel Assignment

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

active comparator: Pecan

2.0 oz pecans daily for 3 months

placebo comparator: Pretzel

3.5 oz pretzel snack daily for 3 months

Interventions

Pecan snack

Pecan

Pretzel snack

Pretzel snack

Primary outcome measure

  • fMRI measures [ Time Frame: baseline and after 3 months ]

Central Contacts and Locations

Central contacts

Chwan-Li (Leslie) Shen, PhD

806-743-2815leslie.shen@ttuhsc.edu

Locations

Texas Tech University Health Sciences Center

Recruiting

Lubbock, Texas, United States, 79430

Contacts

Chadley Coperland

806-743-4752Chadley.Copeland@ttuhsc.edu

More Information

Sponsor

Texas Tech University Health Sciences Center

Last update posted

Sep 8, 2026

Last verified

Sep, 2026

Keywords

  • neuroinflammation
  • gut microbiome
  • fMRI

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Texas Tech University Health Sciences Center on 2026-09-08.