Interaction Between Dairy and Gut Hormone Response on Cognitive Performance in Children.

Interaction Between Milk and Yogurt and Gastrointestinal Hormone Response on Cognitive Performance in School-Aged Children

The purpose of this study is to investigate the short-term effects of milk and yogurt of varying fat and protein content on cognitive performance in healthy children aged 9 - 14 years; and to provide insight into mechanisms by which dairy consumption may affect cognitive performance through gastrointestinal (GI) hormone responses. The investigators hypothesize that the consumption of dairy products, specifically their protein and fat components, will improve cognitive performance via its interaction with the gut-brain axis in children. Furthermore, the investigators hypothesize that all milk and yogurt products will enhance cognitive performance over 120- mins compared to snack skipping through its interaction with GI hormones, with a greater effect in higher fat containing milk and yogurt products.

Study Overview

• Status: Recruiting
• Conditions: Healthy; Children
• Intervention / Treatment: Other: Fat-Free Milk; Other: Low-Fat Milk; Other: Full-fat Milk; Other: Snack Skipping; Other: Fat-Free Yogurt; Other: Low-Fat Yogurt; Other: Full-Fat Yogurt

Detailed Description

A randomized within-subject repeated measures experiment will be used to study the effect of milk and yogurt of varying fat content on cognitive performance and its interaction with GI hormones in children (9-14 years). Participants will consume milk [Experiment A] and yogurt [Experiment B] test treatments, followed by measures of cognitive performance, blood glucose and GI hormone biomarkers over 120-min. In Experiment A and B, participants will consume, in a random order on separate mornings, one of four test treatments: (1) Full-fat, (2) Low-Fat, (3) No-fat, and (4) Snack-skipping test treatments. Cognitive domains (learning and memory, spatial working memory, attention, processing speed, and executive function), gastrointestinal hormone response, and subjective emotions will be assessed at baseline (0-min), and 30-, 60-, and 120-min following treatment consumption.

• Study Type: Interventional
• Enrollment (Estimated): 48
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Canada
  • Ontario
    • Toronto, Ontario, Canada, M5B 2K3
      • Recruiting
      • Toronto Metropolitan University
      • Contact: Nick Bellissimo; Phone Number: 553103 416-979-5000; Email: nick.bellissimo@torontomu.ca

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• 9 to 14 years of age;
• Normal weight is defined as being between the 5th and 85th percentile for age and biological sex at birth according to the Centers for Disease Control growth reference charts

Exclusion Criteria:

• Children with overweight/ obesity;
• Children with food sensitivities or allergies to dairy, gluten or any foods used in the study;
• Children with any diagnosed learning, emotional, or behavioural disabilities;
• Children taking any medications that may influence cognitive performance.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

7

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Fat-Free Milk Treatment; Test Treatment	Other: Fat-Free Milk; Fat-free milk (500 mL, skim, 0%, Lactantia PurFiltre) will provide 180 kcal, 0.4 g fat, 26 g carbohydrate, and 18 g protein. Treatments matched for calories (180 kcal).
Experimental: Low-Fat Milk Treatment; Test Treatment	Other: Low-Fat Milk; Low-free milk (346 mL, 2%, Lactantia PurFiltre) will provide 180 kcal, 6.9 g fat, 16.6 g carbohydrate, and 12.5 g protein. Treatments matched for calories (180 kcal).
Experimental: Full-Fat Milk Treatment; Test Treatment	Other: Full-fat Milk; Full-free milk (281 mL, 3.25%, Lactantia PurFiltre) will provide 180 kcal, 9.0 g fat, 13.5 g carbohydrate, and 10.1 g protein. Treatments matched for calories (180 kcal).
Experimental: Snack Skipping Treatment; Test Treatment	Other: Snack Skipping; Snack skipping (no caloric contribution).
Experimental: Fat-Free Yogurt; Test Treatment	Other: Fat-Free Yogurt; Fat-free Yogurt (242.3 g, Oikos High Protein Vanilla; 0% MF) will provide 180 kcal, 0 g fat, 20.8 g carbohydrate, and 23.5 g protein. Treatments matched for calories (180 kcal).
Experimental: Low-Fat Yogurt; Test Treatment	Other: Low-Fat Yogurt; Low-fat Yogurt (210.0 g, Oikos Original 2% MF) will provide 180 kcal, 3.6 g fat, 21.6 g carbohydrate, and 15.6 g protein. Treatments matched for calories (180 kcal).
Experimental: Full-Fat Yogurt; Test Treatment	Other: Full-Fat Yogurt; Full-fat Yogurt (185.3 g, Oikos Extra Creamy Vanilla 9% MF) will provide 180 kcal, 15.9 g fat, 21.2 g carbohydrate, and 6.4 g protein. Treatments matched for calories (180 kcal).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Learning and short-term memory	Cognitive performance tests will be administered via a Dell tablet (Millisecond, Inquisit Web) and paper/pen. Learning and short-term memory will be assessed using an immediate and delayed Word Recall Test (accuracy).	Immediate measured at 30-minutes post-treatment and delayed at 60- and 120-minutes post-treatment consumption
Spatial working memory	Cognitive performance tests will be administered via a Dell tablet (Millisecond, Inquisit Web) and paper/pen. Spatial working memory will be assessed using the forward and backward versions of the Corsi Block Test (accuracy).	Change from baseline (measured at 0-minutes before treatment) and at 30-minutes, 60-minutes and 120-minutes post-treatment consumption
Sustained Attention	Cognitive performance tests will be administered via a Dell tablet (Millisecond, Inquisit Web) and paper/pen. Sustained attention and processing speed will be assessed using the Continuous Performance Test (CPT) (accuracy).	Change from baseline (measured at 0-minutes before treatment) and at 30-minutes, 60-minutes and 120-minutes post-treatment consumption
Executive Function	Cognitive performance tests will be administered via a Dell tablet (Millisecond, Inquisit Web) and paper/pen. Executive function and selective attention will be assessed using the Flanker Task (accuracy)	Change from baseline (measured at 0-minutes before treatment) and at 30-minutes, 60-minutes and 120-minutes post-treatment consumption

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Subjective mood and emotion	A visual analogue scale (VAS) with twelve questions will be administered to assess subjective emotions and mood (aggression, anger, excitement, disappointment, happiness, upset, frustration, alertness, sadness, tension, calmness, sleepiness, and wellness). Individual questions will be used to form a composite emotion score. Each VAS will be administered via a digital software application (Express VAS, Toronto, Ontario, Canada) on a Dell tablet where children will place an 'X" on the VAS line (100 unit scale) to describe their feelings.	Change from baseline (measured at 0-minutes before treatment) and at 30-minutes, 60-minutes and 120-minutes post-treatment consumption
Gastrointestinal Hormone Response	Blood biomarkers will include glucose, insulin, active GLP- 1, and total GIP. Blood samples will be collected via a venous catheter inserted into the participants arm by a Registered Nurse	Change from baseline (measured at 0-minutes before treatment) and at 30-minutes, 60-minutes and 120-minutes post-treatment consumption

Collaborators and Investigators

• Sponsor: Toronto Metropolitan University
• Collaborators: National Dairy Council; Dairy Management Inc.
• Investigators: Principal Investigator: Nick Bellissimo, PhD, Toronto Metropolitan University

Study record dates

Study Major Dates

• Study Start (Actual): November 15, 2025
• Primary Completion (Estimated): October 1, 2027
• Study Completion (Estimated): October 1, 2027

Study Registration Dates

• First Submitted: November 13, 2025
• First Submitted That Met QC Criteria: November 13, 2025
• First Posted (Estimated): November 17, 2025

Study Record Updates

• Last Update Posted (Estimated): December 9, 2025
• Last Update Submitted That Met QC Criteria: December 2, 2025
• Last Verified: December 1, 2025

More Information

Terms related to this study

• Keywords: Dairy; Emotions; Mood; Cognitive Performance; Gastrointestinal Hormones
• Additional Relevant MeSH Terms: Therapeutics; Diet, Food, and Nutrition; Physiological Phenomena; Nutritional Physiological Phenomena; Diet Therapy; Nutrition Therapy; Diet; Diet, Fat-Restricted
• Other Study ID Numbers: REB 25-066

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

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