Immune Response, Inflammation
Conditions
Keywords
Almonds, Immunity, Inflammation
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
Detailed description
The proposed study is a parallel-group, free-living, observer-blind, randomized controlled dietary intervention trial on 66 overweight middle-aged men and post menopausal women. This study will be carried out in two phases: Phase 1 will examine the effects of almonds on clinically relevant markers of immune function, and Phase 2 will assess the antibody response to influenza vaccination following almond consumption. Participants will attend a baseline clinic and will be randomized to one of two groups. The Almond group will receive 15% of daily energy intake in the form of almonds as a snack and the Control group will continue thier usual diet but completely avoid almonds and restrict other nuts to less than 2 servings per week. The intervention will be for 12 weeks, at which time both group participants will receive the influenza vaccination, and continue the same dietary intervention for another 28 weeks.
Interventions
DIETARY_SUPPLEMENTAlmond group
Participants in the Almond group will receive 15% of their daily energy intake in the form of almonds as a snack
DIETARY_SUPPLEMENTControl Group
The control group will continue their usual diet but will completely avoid almonds and restrict other nuts to less than 2 servings per week
Sponsors
Loma Linda University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)
Masking description
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
Intervention model description
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
Eligibility
Sex/Gender
ALL
Age
40 Years to 70 Years
Healthy volunteers
Yes
Inclusion criteria
* 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
Exclusion criteria
* 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
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| changes in lymphocyte activity and cytokine production | baseline to 12 weeks | 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 |
| changes in serum inflammatory cytokine concentration | baseline to 12 weeks | Changes in the concentrations of the inflammatory cytokines will be performed on serum using enzyme-linked immunoassay (ELISA) |
| changes in complete blood count (CBC) | baseline to 12 weeks | 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 |
| changes in lymphocyte populations | baseline to 12 weeks | Immunophenotyping will be performed by flow cytometry to measure the number of T helper, T cytotoxic, Naïve and memory cells and B cells |
| changes in natural killer (NK) cell activity | baseline to 12 weeks | 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 |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| changes in blood zinc levels | baseline to 12 weeks | Zinc levels in blood will be analyzed in trace element- free tubes and assayed by atomic absorption spectrophotometry using standard reference material obtained from the National Institute of Standards and Technology to check the accuracy and precision of the determinations |
| changes in upper respiratory infection questionnaire score | baseline to 28 weeks | Upper respiratory tract infections will be tracked using the Jackson and Dowling questionnaire. The questionnaire will be completed daily by participants, either manually or electronically , throughout the 28-week study period. The scale for the questionnaire is from 0-42. The higher score means worse outcome. |
Countries
United States
Outcome results
None listed