Almonds, Gut Microbiome and Kids

Official title

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

Overview

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.

Interventions

• 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 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.

Primary outcome measures

• Change in Gut Microbiome Alpha and Beta Diversity Measured by 16S rRNA Gene Sequencing of Fecal Samples [Time frame: 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 [Time frame: Baseline (day 0) and Endpoint (week 8)]
• Change in Fecal Metabolome [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Serum Metabolome [Time frame: Baseline (day 0) and endpoint (week 8)]

Secondary outcome measures (12)

• Change in Gut Transit Time [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Waist/Hip Circumference [Time frame: Baseline (week 0), midpoint (week 4), and endpoint (week 8)]
• Change in Habitual Dietary Intake [Time frame: Baseline (day 0), midpoint (week 4), and endpoint (week 8)]
• Change in Body Weight [Time frame: Baseline (day 0), midpoint (week 4), endpoint (week 8)]
• Change in Urinary Melatonin [Time frame: Baseline (day 0), midpoint (week 4), and endpoint (week 8)]
• Change in Body Fat Percentage [Time frame: Baseline (day 0), midpoint (week 4), and endpoint (week 8)]
• Change in Lipid Profiles [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Biomarkers of Inflammation [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Biomarkers of Intestinal Barrier Function [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Lean Mass [Time frame: Baseline (day 0), midpoint (week 4), and endpoint (week 8)]
• Change in Biomarkers of Appetite [Time frame: Baseline (day 0) and endpoint (week 8)]
• Change in Rested, Seated Blood Pressure [Time frame: Baseline (day 0), midpoint (week 4), and endpoint (week 8)]

Eligibility criteria

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%).

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Open label

Primary purpose

Basic science

Study locations

United States · 1 center

• The Gut Biome Lab — Tallahassee

Identifiers

NCT: NCT07636850 · STUDY00007355

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗