Impact of Peanut Consumption on Stress, Immune Function, Inflammation, and Cardiovascular Health in High-Stress Individuals

OTHER

Peanuts, roasted, salted with skins

42g roasted salted peanuts with skins consumed daily

OTHER

Isocaloric food

Corn chips (45g)

Change in psychosocial stress over time

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

The PSS-10 will be administered 4 times during the study. The 10-item Perceived Stress Scale (PSS-10) is a validated, standard instrument used to assess subjective perceptions of chronic psychological stress (i.e., excessive demands, insufficient coping resources, and a perceived lack of control). The minimum score is 0 and the maximum score is 40. Higher scores indicate greater severity of psychosocial stress.

Change from baseline of allostatic load following dietary interventions

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Before and after each intervention, cumulative physiological stress load, also referred to as allostatic load (AL), will be calculated. AL will be derived from 12-h overnight urinary cortisol, norepinephrine, and epinephrine levels (corrected for urinary creatinine levels), resting systolic and diastolic blood pressure, and overnight fasted waist-to-hip ratio, fasting serum levels of high-sensitivity C-reactive protein (hs-CRP), cholesterol, HDL-cholesterol, fasting plasma dehydroepiandrosterone sulfate (DHEA-S), and whole blood glycohemoglobin (HbA1c).

Change from baseline of monocyte gene expression

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Total monocytes isolated from human peripheral blood mononuclear cells (PBMCs) at baseline and post-intervention will be collected, and their global gene expression will be analyzed by ribonucleic acid (RNA) sequencing.

Change from baseline of cytokine and interferon production in PBMCs

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Monocytes isolated from human peripheral blood mononuclear cells (PBMCs) will be challenged with and without toll-like receptor ligands to assess cytokine and interferon production in low- and high-stress subjects at baseline and after intervention.

Change from baseline of cytotoxicity of peripheral natural killer cells

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

The cytotoxicity of peripheral natural killer (NK) cells isolated from subject's peripheral blood mononuclear cells (PBMCs) of low- and high-stress individuals at baseline and after intervention will be assessed using an ex vivo cytotoxicity assay with human erythroleukemic cell line (K562) target cells.

Change from baseline of interferon-gamma

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Interferon-gamma (IFN-γ) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of tumor necrosis factors alpha and beta

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Tumor necrosis factors alpha and beta (TNF-α, TNF-β) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of interleukins

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

A panel of interleukins: (IL) (IL-1α, IL-1β, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-10, IL-12/IL-23p40, IL-12p70, IL-13, IL-15, IL-16, IL-17A) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of fibroblast growth factor

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Fibroblast growth factor (FGF) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of granulocyte-macrophage colony-stimulating factor

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Granulocyte-macrophage colony-stimulating factor (GM-CSF) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery:

Change from baseline of thymus and activation-regulated chemokine

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Thymus and activation-regulated chemokine (TARC). will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of macrophage inflammatory proteins-1 alpha and beta

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Macrophage inflammatory proteins-1 alpha and beta (MIP-1α, MIP-1β) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of macrophage-derived chemokine

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Macrophage-derived chemokine (MDC) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of monocyte chemoattractant proteins-1 and -4

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Monocyte chemoattractant proteins-1 and -4 (MCP-1, MCP-4) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of interferon gamma-induced protein-10

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Interferon gamma-induced protein-10 (IP-10) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of eotaxin and eotaxin-3

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Eotaxin and eotaxin-3 will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of C-reactive protein

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

C-reactive protein (CRP) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of intercellular adhesion molecule-1

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Intercellular adhesion molecule-1 (ICAM-1) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of placental growth factor

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Placental growth factor (PlGF) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of serum amyloid A

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Serum amyloid A (SAA) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of angiopoietin-1 receptor

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Angiopoietin-1 receptor (Tie-2) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of vascular cell adhesion molecule-1

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Vascular cell adhesion molecule-1 (VCAM-1) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of vascular endothelial growth factors A, C, and D

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Vascular endothelial growth factors A, C, and D (VEGF-A, VEGF-C, VEGF-D) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of vascular endothelial growth factor receptor-1

Time frame: Baseline, 4 weeks, 8 weeks, and 12 weeks

Vascular endothelial growth factor receptor-1 (VEGFR-1/Flt-1) will be measured before and after each intervention using the V-PLEX Human Biomarker 40-Plex Kit from Meso Scale Discovery

Change from baseline of monocyte phenotype

Time frame: Baseline, 4 weeks, 8 weeks, 12 weeks

Classical monocytes, intermediate monocytes, and non-classical monocytes, will be identified by leukocyte common antigen (CD45+), Low-density lipoprotein receptor-related protein 1 (CD91+), cluster of differentiation 14 (CD14), cluster of differentiation 16 (CD16), and cluster of differentiation 3 (lin-CD3)/cluster of differentiation 66b (CD66b)/neural cell adhesion molecule (CD56)/cluster of differentiation 19 (CD19) using flow cytometry.

Change from baseline of monocyte functional profile

Time frame: Baseline, 4 weeks, 8 weeks, 12 weeks

Cellular activation of classical monocytes, intermediate monocytes, and non-classical monocytes will be assessed by expression of cluster of differentiation 11b (CD11b) and cluster of differentiation 163 (CD163).

Change from baseline of natural killer cell phenotype

Time frame: Baseline, 4 weeks, 8 weeks, 12 weeks

Natural killer (NK) cells will be identified by CD45+, cluster of differentiation 56+ (CD56+), and lin-CD3/CD66b/CD14/CD19 using flow cytometry.

Change from baseline of natural killer cell functional profile

Time frame: Baseline, 4 weeks, 8 weeks, 12 weeks

Natural killer (NK) cell maturation status and cytotoxic potential via CD16, cluster of differentiation 57 (CD57), killer cell lectin-like receptor K1 (NKG2D), and cluster of differentiation 159 (NKG2A) will be analyzed using flow cytometry.

What is a clinical trial?

A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.

Is it safe to participate?

Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.

Will I be compensated?

Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.

Will I receive a placebo instead of treatment?

When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.

Can I leave a trial if I change my mind?

Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.

How long does a clinical trial last?

Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.