Walnut and Immunity Study

NCT05915390 | Completed

• 1 other identifier: 5220423
• Study Type: interventional
• Target: 52
• Locations: 1 country
• Sites: 1

Brief Summary

The main objective of the study is to determine if eating walnuts enhances immune function, in older free-living men and postmenopausal women with overweight.

Conditions

Immune Response; Upper Respiratory Tract Infection

Keywords

walnuts; Immunity; Inflammation

Outcome Measures

Primary Outcomes (8)

• changes in lymphocyte populations

  Immunophenotyping will be performed by flow cytometry to measure the number of T helper, T cytotoxic, Naïve and memory cells and B cells

  baseline to 12 weeks

• changes in lymphocyte activity

  The production of lymphocytes will be measured in the supernatant using Enzyme linked immunosorbent assay (ELISA)

  baseline to 12 weeks

• changes in cytokine production

  The cytokines produced due to lymphocyte activity will be measured in the supernatant using Enzyme linked immunosorbent assay (ELISA)

  baseline to 12 weeks

• changes in serum inflammatory cytokine concentration

  changes in the concentrations of the inflammatory cytokines will be performed on serum using enzyme-linked immunoassay (ELISA) will include hs-CRP, interleukin (IL)-1β, IL-6, TNF-α, IL-10, and IL-4.

  baseline to 12 weeks

• changes in diversity of immune-modulating and butyrate -producing gut bacteria in feces

  DNA extraction from stool samples will be performed using QIAamp DNA Stool Mini kits.69 The QIIME (Quantitative Insights Into Microbial Ecology) software will be used to analyze 16S rRNA gene sequences and determine the effect of the intervention on microbial diversity at the phylum, genus, and operational taxonomic unit levels.

  baseline to 12 weeks

• Changes in concentration of Immunoglobulin A in feces

  changes in Immunoglobulin A will be determined using high performance liquid chromatography-mass spectrometry (HPLC-MS)

  baseline to 12 weeks

• Changes in concentration of Calprotectin in feces

  changes in Calprotectin will be determined using high performance liquid chromatography-mass spectrometry (HPLC-MS)

  baseline to 12 weeks

• Changes in concentration of small chain fatty in feces

  changes in Small chain fatty acids will be determined using high performance liquid chromatography-mass spectrometry (HPLC-MS)

  baseline to 12 weeks

Secondary Outcomes (1)

• changes in upper respiratory infection questionnaire score

  baseline to 12 weeks

Study Arms (2)

walnut group

ACTIVE COMPARATOR

walnut group will receive 15% of their total energy as walnuts

Dietary Supplement: walnuts

control group

ACTIVE COMPARATOR

continue with habitual diet and abstain from eating walnuts

Dietary Supplement: Habitual diet

Interventions

walnuts DIETARY_SUPPLEMENT

walnuts will provide 15% of the total energy

walnut group

Habitual diet DIETARY_SUPPLEMENT

continue with habitual diet and abstain from walnuts

control group

Eligibility Criteria

• Age: 55 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Older men and post-menopausal women aged 55-75 years
• Have a BMI of 25-32
• Being able to commute to Loma Linda University.
• Not taking medication or supplements that affect immunity

You may not qualify if:

• Intolerance or allergy to walnuts
• Regular intake of walnuts and/or other nuts (\>3 ounces per week).
• Immune system insufficiency or disease.
• Using immune boosting supplements.
• Exposure to antibiotics and corticoids immediately prior to the study.
• Participants with uncontrolled chronic diseases, and relevant psychiatric illness, including major depression will not be included in study
• Flu vaccination or Covid booster within past 6 months

Sponsors & Collaborators

• Loma Linda University: lead

Study Sites (1)

Loma Linda University School of Public Health

Loma Linda, California, 92350, United States

Location

MeSH Terms

Conditions

Respiratory Tract Infections; Inflammation

Condition Hierarchy (Ancestors)

Infections; Respiratory Tract Diseases; Pathologic Processes; Pathological Conditions, Signs and Symptoms

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: INVESTIGATOR, OUTCOMES ASSESSOR
• Masking Details: The investigator and outcome assessor will not be aware which participant is in what arm. The participant and the care provider will know about the treatment allocation
• Purpose: PREVENTION
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor Nutrition and Epidemiology

Model Details: This will be a parallel, free-living, randomized controlled trial with 54 men and post-menopausal women

Study Record Dates

• First Submitted: May 16, 2023
• First Posted: June 23, 2023
• Study Start: June 27, 2023
• Primary Completion: December 18, 2023
• Study Completion: December 18, 2023
• Last Updated: October 2, 2024

Record last verified: 2024-09

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)