The Effect of Dairy Intake on Body Weight and Composition and Metabolic Health in Adolescents and Seniors
1 other identifier
interventional
240
1 country
2
Brief Summary
The goal of this study is to examine how regular dairy intake affects body weight, body composition, and metabolic health in overweight and obese adolescents (ages 15-18) and older adults (ages 60-80) over six months. We are inviting eligible individuals to participate in this study at the Nutrition Intervention Center, Department of Nutritional Sciences, University of Toronto. Participants will be randomly divided into two groups. The intervention (dairy) group will consume three servings of dairy per day (milk, yogurt, and cheese) before breakfast, lunch, and dinner. The control (low-dairy) group will continue their usual diet, keeping dairy intake to less than one serving per day. Participants will have biweekly sessions with a registered dietitian to be guided to follow Canada's Food Guide, monitor their dietary intake and ensure compliance with their assigned group. In addition, they will visit the Nutrition Intervention Center at weeks 0, 12, and 24 for anthropometric and body composition assessments (weight, height, waist circumference, blood pressure, lean mass, and fat mass), resting metabolic rate, (gait speed, grip strength, and chair stand test just for older adults) and blood markers (fasting blood glucose, insulin, C-peptide, HbA1c, lipid profiles, and inflammatory markers). Each visit will take approximately 4 hours. Before each visit, the participants will be asked to fast overnight for 12 hours, maintain their usual diet and sleep patterns, and avoid exercise and alcohol the day before. The participants will be compensated for their time and travel expenses. Our secondary objective is to compare the effects of dairy and plant-based alternative products on blood sugar and appetite regulation in adolescents and older adults. Participants will be asked to come to the Nutrition Intervention Center on 3 separate occasions: once for an in-person screening lasting approximately 30 min and 2 times for study visits lasting approximately 2.5 hrs each. The entire study will take at least 2 weeks to complete. You will be asked to fast for 12 hrs (overnight) before each study visit. You will also be instructed to maintain the same dietary and sleep patterns and refrain from exercise and alcohol consumption on the days before the study visits. During these study visits, you will be asked to consume either a dairy or a plant-based alternative product as well as a pizza meal. You will periodically fill out questionnaires rating your feelings and perceptions, and provide blood samples through finger pricks and intravenously through your forearm to measure blood sugar, insulin, hormones, and amino acids. You will be compensated for your time and travel expenses.
Trial Health
Trial Health Score
Automated assessment based on enrollment pace, timeline, and geographic reach
participants targeted
Target at P75+ for not_applicable
Started Jun 2026
Typical duration for not_applicable
2 active sites
Health score is calculated from publicly available data and should be used for screening purposes only.
Trial Relationships
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Study Timeline
Key milestones and dates
First Submitted
Initial submission to the registry
March 10, 2025
CompletedFirst Posted
Study publicly available on registry
March 17, 2025
CompletedStudy Start
First participant enrolled
June 1, 2026
ExpectedPrimary Completion
Last participant's last visit for primary outcome
June 1, 2027
Study Completion
Last participant's last visit for all outcomes
June 1, 2028
March 5, 2026
March 1, 2026
1 year
March 10, 2025
March 3, 2026
Conditions
Keywords
Outcome Measures
Primary Outcomes (4)
Body Fat Mass (kg)
Body Fat Mass (BFM) is the primary outcome in the long-term study of the senior group. It will be measured using bioelectrical impedance analysis (BIA).
BFM will be measured at weeks 0, 6, 12, 18, and the end of the study (week 24).
Lean body mass (Kg)
Lean body mass (LBM) is the primary outcome in the long-term study of the senior group. It will be measured using bioelectrical impedance analysis (BIA).
LBM will be measured at weeks 0, 6, 12, 18, and the end of the study (week 24).
Body Mass Index (BMI) z-score
BMI z-score, the primary outcome in the long-term study of the adolescent group, is an age- and sex-adjusted measure of BMI in adolescents. It will be calculated using height and weight measurements and interpreted using WHO growth charts and percentiles.
BMI z-score will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
Blood Glucose (mmol/L) (short-term study)
Blood glucose, the primary outcome in the short-term studies of adolescents and seniors, will be measured via finger-prick using a glucometer at 0, 5, 20, 35, 50, 65, 95, 125, and 145 minutes after treatment consumption.
Over 145 minutes after treatment consumption at each session, for a total of 2 weekly sessions.
Secondary Outcomes (27)
Fasting blood glucose (FBG) (mmol/L)
FBS will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
HbA1c (%)
HbA1c will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
Insulin (µU/mL)
Insulin will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
C-Peptide (pmol/L)
C-Peptide will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
Homeostatic Model Assessment of Insulin Resistance (HOMA-IR)
HOMA-IR will be measured at the beginning (week 0), midpoint (week 12), and end of the study (week 24).
- +22 more secondary outcomes
Other Outcomes (1)
Dietary intake
Three-day food records will be collected every six weeks; the mCFIS and CEPS will be administered monthly; and the KAPQ will be administered at weeks 0, 12, and 24.
Study Arms (8)
High Dairy - Adolescents (long-term study)
EXPERIMENTALParticipants in the intervention group will follow Canada's Food Guide and consume 3 servings of dairy per day.
Low Dairy- Adolescents (long-term study)
ACTIVE COMPARATORParticipants in the control group will adhere to Canada's Food Guide and keep their dairy intake to less than one serving per day.
High Dairy - Seniors (long-term study)
EXPERIMENTALParticipants in the intervention group will follow Canada's Food Guide and consume 3 servings of dairy per day.
Low Dairy- Seniors (long-term study)
ACTIVE COMPARATORParticipants in the control group will adhere to Canada's Food Guide and keep their dairy intake to less than one serving per day.
Dairy arm - Adolescents (short-term study)
EXPERIMENTALParticipants will consume 2 servings of dairy milk or yogurt.
Plant-based alternative - Adolescents (short-term study)
EXPERIMENTALParticipants will consume 2 servings of a commercially available soy milk or plant-based yogurt.
Dairy arm - Seniors (short-term study)
EXPERIMENTALParticipants will consume 2 servings of dairy milk or yogurt.
Plant-based alternative - Seniors (short-term study)
EXPERIMENTALParticipants will consume 2 servings of a commercially available soy milk or plant-based yogurt.
Interventions
Participants aged 15-18 and 60-80 years who are randomly assigned to the intervention group will follow Canada's Food Guide and consume 3 servings of dairy (milk, yogurt, cheese) per day for 24 weeks.
The dairy products that participants will be required to consume include: 1) Trial 1: 2% cow's milk; 2) Trial 2: dairy yogurt.
Participants will be instructed to follow Canada's Food Guide.
The plant-based products that participants will be required to consume include: 1) Trial 1: soy beverage; 2) Trial 2: plant-based yogurt;
Eligibility Criteria
You may qualify if:
- Age 15-18 years old (adolescents) or 60-80 years old (seniors)
- BMI z-score \>+1SD, \<+2SD (adolescents) or BMI 25-34.9 kg/m2 (seniors)
- Waist circumference \> 80 cm for women and \> 94 cm for men (seniors)
- FBG 5.6-6.9 mmol/L (prediabetes)
- Willing to follow Canada's Food Guide
- Willing to maintain current dietary supplement use throughout the study.
- Willing to abstain from alcohol consumption for 24 hours before all test visits.
- Willing to avoid vigorous physical activity for 24 hours before all test visits.
- Understands the study procedures and is willing to provide informed consent by the parent/guardian and assent by participant to participate in the study and authorization to release relevant protected health information to the study investigator.
You may not qualify if:
- Fasting BG ≥ 7 mmol/L
- Blood pressure systolic ≥ 130mmHg or diastolic ≥ 80mmHg (adolescents) or systolic ≥ 140 mmHg or diastolic pressure ≥ 90 mmHg
- Smoking (tobacco and/or cannabis product use in the last 6 months)
- Thyroid problems
- History of CVDs, diabetes, liver or kidney disease, inflammatory bowel disease, celiac disease, short bowel syndrome, any malabsorption syndrome, pancreatitis, gallbladder, or biliary disease.
- Presence of gastrointestinal disorder or surgeries within the past year.
- Use of the prescription or non-prescription drugs, herbal or nutritional supplements known to affect the outcome of the study as per the investigator's judgment (including prebiotics and probiotics).
- Known to be pregnant, lactating, or not postmenopausal for at least a year and/or is taking hormonal treatments
- Unwillingness or inability to comply with the experimental procedures
- Known intolerance, sensitivity, or allergy to dairy, gluten, or any other study treatments.
- Consumption of protein powders/supplements
- Extreme dietary habits (e.g., Atkins diet, very high-protein diets, etc.)
- Weight gain or loss of \> 5% in the previous three months.
- Excessive alcohol intake (more than 2 drinks per day or 9 per week)
- Restrained eating, identified by a score of ≥11 on the Eating Habits Questionnaire
- +22 more criteria
Contact the study team to confirm eligibility.
Sponsors & Collaborators
Study Sites (2)
Department of Nutritional Sciences
Toronto, Ontario, M5S 1A8, Canada
Nutrition Intervention Center
Toronto, M5S 3H2, Canada
MeSH Terms
Conditions
Condition Hierarchy (Ancestors)
Study Officials
- PRINCIPAL INVESTIGATOR
G Harvey Anderson, Ph.D.
University of Toronto
Central Study Contacts
Study Design
- Study Type
- interventional
- Phase
- not applicable
- Allocation
- RANDOMIZED
- Masking
- TRIPLE
- Who Masked
- PARTICIPANT, CARE PROVIDER, OUTCOMES ASSESSOR
- Purpose
- PREVENTION
- Intervention Model
- PARALLEL
- Sponsor Type
- OTHER
- Responsible Party
- PRINCIPAL INVESTIGATOR
- PI Title
- Professor
Study Record Dates
First Submitted
March 10, 2025
First Posted
March 17, 2025
Study Start (Estimated)
June 1, 2026
Primary Completion (Estimated)
June 1, 2027
Study Completion (Estimated)
June 1, 2028
Last Updated
March 5, 2026
Record last verified: 2026-03
Data Sharing
- IPD Sharing
- Will not share
IPD will not be shared, as all data will be de-identified and pooled during the analysis. Only researchers directly involved in the study will have access to the data.