Effect of Almonds on Immune Strength and Response to Flu Vaccination in Overweight Older Men and Postmenopausal Women: A Randomized Controlled Study

NCT05031663 | Completed

• 1 other identifier: 5210259
• Study Type: interventional
• Target: 61
• Locations: 1 country
• Sites: 1

Brief Summary

This research study will test the effects of almonds on immune functions and immune response to influenza vaccine in overweight middle-aged men and postmenopausal women

Conditions

Immune Response; Inflammation

Keywords

Almonds; Immunity; Inflammation

Outcome Measures

Primary Outcomes (5)

• 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 and cytokine production

  PBMC cells will be separated from blood, activated and cultured using phytohemagglutinin (PHA). Inflammatory cytokine production will be measured in the resulting supernatant using ELISA

  baseline to 12 weeks

• changes in natural killer (NK) cell activity

  The NK degranulation assay will be performed on blood samples. The test will be conducted using a modified flow cytometry method that measures the expression of CD107a

  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)

  baseline to 12 weeks

• changes in complete blood count (CBC)

  changes in the complete blood count will be performed on whole blood with the use of an automated hematology analyzer at a certified clinical facility

  baseline to 12 weeks

Secondary Outcomes (2)

• changes in upper respiratory infection questionnaire score

  baseline to 28 weeks

• changes in blood zinc levels

  baseline to 12 weeks

Study Arms (2)

Almonds

EXPERIMENTAL

The almond group will receive 15% of their daily energy intake in the form of almonds

Dietary Supplement: Almond group

Control

PLACEBO COMPARATOR

The control group will be encouraged to continue their usual diet but completely avoid almonds and restrict other nuts to less than 2 servings per week

Dietary Supplement: Control Group

Interventions

Control Group DIETARY_SUPPLEMENT

The control group will continue their usual diet but will completely avoid almonds and restrict other nuts to less than 2 servings per week

Control

Almond group DIETARY_SUPPLEMENT

Participants in the Almond group will receive 15% of their daily energy intake in the form of almonds as a snack

Almonds

Eligibility Criteria

• Age: 40 Years - 70 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Overweight men and post menopausal women (Basal Metabolic Index 25-32)
• Age limit between 40-70 years
• Be able to commute to Loma Linda University

You may not qualify if:

• Intolerance or allergy to almonds
• Bad dentures, inability to chew almonds
• Regular intake of almonds and or other nuts
• Use of immune boosting supplements
• Exposure to antibiotics and corticosteroids immediately prior to study
• Have received influenza vaccination in past 10 months
• Uncontrolled chronic disease and psychiatric illness

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

Inflammation

Interventions

Control Groups

Condition Hierarchy (Ancestors)

Pathologic Processes; Pathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Epidemiologic Research Design; Epidemiologic Methods; Investigative Techniques; Research Design; Methods

Study Officials

• Joan Sabate, DrPh

  Loma Linda University

  PRINCIPAL INVESTIGATOR

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 of Nutrition

Model Details: this will be a parallel, free-living, randomized controlled trial, where 66 middle-aged men and post menopausal women will be randomized to receive either the almonds or control

Study Record Dates

• First Submitted: July 6, 2021
• First Posted: September 2, 2021
• Study Start: August 12, 2021
• Primary Completion: May 10, 2023
• Study Completion: May 10, 2023
• Last Updated: December 9, 2025

Record last verified: 2025-12

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)