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.