Almonds, Gut Microbiome and Kids

Nutritional Impact of Almond Butter on Gut Microbiome and Cardiometabolic Health in School-Aged Children: A Novel and Timely Pilot Randomized Controlled Trial

This 8-week parallel-arm randomized controlled trial (N=70; ages 6-13) will determine the impact of daily almond butter consumption on gut microbiome composition and function, intestinal barrier integrity, and cardiometabolic health in school-aged children. Participants will be randomized to either a once-daily snack of personalized-portion almond butter (ALB; 16g, Creamy Natural Almond Butter) or an isocaloric nut-free chocolate spread control (CTL; 16g, Cadbury Milk Chocolate), each served on two plain unsalted saltine crackers, added to their habitual diet. The primary outcomes include oro-gut microbial composition and diversity, gut microbial functional capacity and metabolomics (SCFAs, bile acids, amino acid metabolites), and intestinal barrier integrity. Secondary outcomes include fasting cardiometabolic markers, systemic inflammation, appetite-regulatory and metabolic hormones, and sleep-related biomarkers. Feasibility, adherence (weekly logs; serum α-tocopherol), and precision nutrition potential will also be assessed, with stratified analyses by age, sex, BMI, ethnicity, and pubertal stage.

This pilot trial will generate the first multi-omics characterization of almond butter's effects on the gut-immune-metabolic axis in children.

Study Overview

• Status: Recruiting
• Conditions: Dysbiosis; Cardiometabolic Health Indicators
• Intervention / Treatment: Other: Cadbury Milk Chocolate Spread; Other: Creamy Richards 100% Almonds! Creamy Natural Almond Butter

• Study Type: Interventional
• Enrollment (Estimated): 70
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: FSU College of Education, Health and Human Services; Phone Number: 850-644-1829; Email: healthandhumansciences@fsu.edu
• Study Contact Backup: Name: Rayven Nairn, MS, RD; Phone Number: 850-644-1829; Email: rsn25b@fsu.edu

Study Locations

• United States
  • Florida
    • Tallahassee, Florida, United States, 32306
      • Recruiting
      • The Gut Biome Lab
      • Contact: Ravinder Nagpal, PhD; Phone Number: 850-644-1829; Email: rnagpal@fsu.edu
      • Sub-Investigator: Cole Patoine, MS, RD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• Enrolled in elementary or middle school (grades 1-8)
• Aged 6-13 years old
• Ability to speak and read in English

Exclusion Criteria:

• Intake of antibiotics in the last 3 months
• Intake of pre/pro/postbiotics in the last 3 months

• Food allergy to study foods

  ◦ Any allergy to nuts or almonds

• Any allergy to the isocaloric snack (chocolate or wheat)
• Regular consumption of nuts or almonds greater than 2 servings / week
• Gastrointestinal disease (ulcerative colitis, Crohn's disease, diverticulosis, peptic ulcers, small intestinal bacterial overgrowth, short bowel syndrome, irritable bowel syndrome, gastroesophageal reflux disease), neurological (multiple sclerosis, meningitis, recent stroke) or endocrine disorders (uncontrolled thyroid disorders, growth hormone disorders, adrenal gland disorders, uncontrolled diabetes - A1C > 9%).

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control Snack Condition; Control (CTL) Group: This condition includes a normal diet supplemented daily with an isocaloric amount of a nut-free, vegetable oil-based chocolate spread (Cadbury Milk Chocolate) also sandwiched between two plain unsalted saltine crackers (Unsalted Tops Premium Saltine Crackers), with the same 16g limit per two crackers. The quantity of chocolate spread provided daily will be equivalent to 20% of each participant's individual daily caloric intake. These caloric needs will be established using Dietary Guidelines for Americans (DGA) based on the participant's age and gender	Other: Cadbury Milk Chocolate Spread; Control (CTL) Group: Participants in this group will receive a daily snack consisting of an isocaloric amount of a nut-free, vegetable oil-based chocolate spread ("Cadbury Milk Chocolate") spread between two plain unsalted saltine crackers ("Unsalted Tops Premium Saltine Crackers"). Similar to the peanut butter group, the chocolate spread will be limited to 16g per two crackers, with additional crackers provided if needed.; Other Names: Control; CTL; Isocaloric spread
Experimental: Almond Butter Condition; Participants in the ALB group will maintain their habitual diet supplemented with a once-daily snack of smooth natural almond butter (Creamy Richards 100% Almonds! Creamy Natural Almond Butter) spread between two plain unsalted saltine crackers (Unsalted Tops Premium Saltine Crackers), with a maximum of 16g of almond butter per two crackers. The daily portion of almond butter will be individualized to provide 20% of each participant's estimated daily caloric needs, calculated using Dietary Guidelines for Americans (DGA) age- and sex-specific energy requirements.	Other: Creamy Richards 100% Almonds! Creamy Natural Almond Butter; Almond Butter (ALB) Group: Participants in this group will receive a daily snack consisting of a personalized portion of smooth natural almond butter (Creamy Richards 100% Almonds! Creamy Natural Almond Butter) spread between two plain unsalted saltine crackers (Unsalted Tops Premium Saltine Crackers). The amount of almond butter will be limited to 16g per two crackers; additional crackers will be provided if the personalized portion exceeds this limit.; Other Names: ALB; Almond Butter

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Gut Microbiome Alpha and Beta Diversity Measured by 16S rRNA Gene Sequencing of Fecal Samples	Freshly voided fecal samples will be collected and DNA extracted using the PowerFecal Pro DNA kit. The V3-V4 hypervariable region of the bacterial 16S ribosomal RNA gene will be PCR-amplified and sequenced. Sequences will be processed using the QIIME2 software package to assess microbial diversity (alpha and beta diversity) and taxonomic composition.	Baseline (day 0), midpoint (week 4) and endpoint (week 8)
Change in Oral Microbiome Alpha and Beta Diversity Measured by 16S rRNA Gene Sequencing of Oral Swabs	Oral biofilm swabs (omniswab - tongue, palate, cheek/lip lining, gums) and unstimulated saliva will be collected in 5ml tubes. DNA will be extracted and the V3-V4 region of the bacterial 16S ribosomal RNA gene PCR-amplified and sequenced. Sequences will be processed using the QIIME2 software package to assess oral microbial diversity (alpha and beta diversity) and taxonomic composition.	Baseline (day 0) and Endpoint (week 8)
Change in Fecal Metabolome	The endpoint of fecal metabolomics will be assessed by collecting fecal samples from participants at the beginning and end of the study. These samples will be analyzed using advanced techniques, such as mass spectrometry, to identify and quantify various metabolites present in the feces. The changes in the levels of specific metabolites, which can reflect shifts in gut microbiome composition and metabolic health, will be compared between pre- and post-intervention periods. This analysis will help determine how regular almond butter intake affects metabolic processes and gut health.	Baseline (day 0) and endpoint (week 8)
Change in Serum Metabolome	The endpoint of serum metabolomics will be assessed by collecting blood serum from participants at the beginning and end of the study. These samples will be analyzed using advanced techniques, such as mass spectrometry, to identify and quantify various metabolites present in the serum. The changes in the levels of specific metabolites, which can reflect shifts in gut microbiome composition and metabolic health, will be compared between pre- and post-intervention periods. This analysis will help determine how regular almond butter intake affects metabolic processes and gut health.	Baseline (day 0) and endpoint (week 8)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Gut Transit Time	Evaluate changes in gut transit time after almond butter or control snack consumption from baseline to final analysis, using a blue-dye capsule.	Baseline (day 0) and endpoint (week 8)
Change in Waist/Hip Circumference	Evaluate changes in waist and hip circumference (centimeters), as well as waist-hip ratio at each study visit before, after and during almond butter consumption, compared to a control snack.	Baseline (week 0), midpoint (week 4), and endpoint (week 8)
Change in Habitual Dietary Intake	Assess changes in habitual dietary intake via 3-day food logs, analyzed using nutrient analysis software (NDSR).	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Body Weight	The endpoint of body weight (kg) will be measured at each visit to assess changes in weight before and after 8 week consumption of almond butter or a control snack spread.	Baseline (day 0), midpoint (week 4), endpoint (week 8)
Change in Urinary Melatonin	Changes in melatonin (urine metabolite 6-sulphatoxymelatonin) will be assessed before, during and after 8-week consumption of almond butter or control snack spread.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Body Fat Percentage	Evaluate changes in body composition, including fat mass, expressed as a percentage of total weight (%). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during almond butter or control snack consumption.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Lipid Profiles	Relevant biomarkers are to be collected via venous blood samples to determine changes in cardiometabolic health including HDL, LDL, total cholesterol, and triglycerides. All will be expressed in units of mg/dL.	Baseline (day 0) and endpoint (week 8)
Change in Biomarkers of Inflammation	Relevant biomarkers are to be collected via venous blood samples to determine changes in inflammation, including but not limited to C-reactive protein (CRP), IL-1 (Interleukin-1), IL-1 beta, IL-6, IL-10, IL-17, IL-23, Tumor Necrosis Factor Alpha (TNF-a), Interferon-gamma (IFN-Y). All will be expressed in units of pg/mL.	Baseline (day 0) and endpoint (week 8)
Change in Biomarkers of Intestinal Barrier Function	Relevant biomarkers are to be collected via venous blood samples to determine changes in intestinal barrier function including LPS (lipopolysaccharides), LBP (lipopolysaccharide binding protein), CD14, Secretory IgA. All will be expressed in units of pg/mL.	Baseline (day 0) and endpoint (week 8)
Change in Lean Mass	Evaluate changes in body composition, including lean mass (kg). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during almond butter or control snack consumption.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Biomarkers of Appetite	Relevant biomarkers are to be collected via venous blood samples to determine changes in appetite including Insulin, Glucagon, glucagon-like peptide 1 (GLP-1), Adiponectin, Leptin, Ghrelin, and Peptide YY. All will be expressed in units of pg/mL.	Baseline (day 0) and endpoint (week 8)
Change in Rested, Seated Blood Pressure	This outcome measure will measure changes in blood pressure taken at rest in the seated position at each visit, before during and after almond butter or control snack consumption, expressed as systolic over diastolic blood pressure in units of millimeters of mercury (mmHg).	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Fasting Blood glucose	Venous blood samples will be collected to determine changes in fasting blood glucose (expressed as mg/DL).	Baseline (day 0) and endpoint (week 8)
Dietary Adherence	Assess adherence to the intervention and control snack throughout the study, as determined by dietary adherence logs kept by the participants each week. Adherence is expressed as a daily percent (%) consumption of their assigned snack	Daily, baseline (day 0) through endpoint (week 8)
Change in Total Body Water	Evaluate changes in body composition, including, total body water (L). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during almond butter or control snack consumption.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Intracellular Fluid	Evaluate changes in body composition, including intracellular fluid (L). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during almond butter or control snack consumption.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)
Change in Extracellular Fluid	Evaluate changes in body composition, including extracellular fluid (L). This is assessed using a bioimpedance spectroscopy device (ImpediMed SBF7) at each study visit before, after and during almond butter or control snack consumption.	Baseline (day 0), midpoint (week 4), and endpoint (week 8)

Collaborators and Investigators

• Sponsor: Florida State University
• Collaborators: Almond Board of California
• Investigators: Principal Investigator: Ravinder Nagpal, PhD, Florida State University

Publications and helpful links

Helpful Links

• Lab Website

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 31, 2028
• Study Completion (Estimated): December 31, 2028

Study Registration Dates

• First Submitted: June 1, 2026
• First Submitted That Met QC Criteria: June 5, 2026
• First Posted (Actual): June 9, 2026

Study Record Updates

• Last Update Posted (Actual): June 9, 2026
• Last Update Submitted That Met QC Criteria: June 5, 2026
• Last Verified: May 1, 2026

More Information

Terms related to this study

• Keywords: pediatric; children; gut microbiome; sleep quality; gut; metabolomics; almonds; nuts; almond butter
• Additional Relevant MeSH Terms: Nervous System Diseases; Mental Disorders; Pathologic Processes; Sleep Wake Disorders; Sleep Disorders, Intrinsic; Dyssomnias; Pathological Conditions, Signs and Symptoms; Dysbiosis; Sleep Initiation and Maintenance Disorders
• Other Study ID Numbers: STUDY00007355

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO
• IPD Plan Description: Deidentified IPD will not be retain past three years, at the time of this submission the researchers does not plan to make IPD available

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No