The purpose of the Dairy vs Plant study is to compare the effects of dairy and plant-based alternative products on blood sugar regulation and nutrient quality in adolescents and older adults. We are inviting healthy, non-diabetic participants aged 14-18 and 60-75, both males and females to participate. The study will take place in the Nutrition Intervention Center located at the Department of Nutritional Sciences, University of Toronto St. George campus. Participants will be asked to come to the Nutrition Intervention Center on 3 separate occasions: once for an in-person screening lasting approximately 30min and 2 times for study visits lasting approximately 2.5 hrs each. The entire study will take a minimum of 2 weeks to complete. You will be asked to fast for 12hrs (overnight) prior to each study visit. You will also be instructed to maintain the same dietary and sleep patterns, refrain from exercise and alcohol consumption 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 forearm to measure blood sugar, insulin, hormones, and amino acids. You will be compensated for your time and travel expenses.
Age 14-18 years old (adolescents) or 60-75 years old (older adults)
BMI z-score >+1SD, <+2SD (adolescents) or BMI 25-30 kg/m2 (older adults)
Willing to maintain habitual diet, physical activity pattern, and body weight throughout the study.
Willing to maintain current dietary supplement use throughout the study. On study visit days, subject agrees not to take any supplements until dismissal from the Nutrition Intervention Center.
Smoking
Thyroid problems
Lactose intolerance and/or allergies, intolerances, or sensitivities to study treatments
Previous history of cardiovascular disease, diabetes, liver or kidney disease, inflammatory bowel disease, celiac disease, short bowel syndrome, malabsorptive syndrome, pancreatitis, gallbladder or biliary disease
Crossover
Dairy
Other interventionThe dairy products that participants will be required to consume include: 1) Trial 1: 2% cow's milk; 2) Trial 2: dairy yogurt; 3) Trial 3: 2% cottage cheese; 4) Trial 4: 2% cow's milk; and 5) Trial 5: isolated whey protein beverage. Participants will only be enrolled in 1 of the 5 trials; as such, they will only consume the 1 dairy product in that trial.
Plant-based alternative
Other interventionThe plant-based products that participants will be required to consume include: 1) Trial 1: soy beverage; 2) Trial 2: plant-based yogurt; 3) Trial 3: tofu; 4) Trial 4: 2% simulated milk; and 5) Trial 5: isolated soy protein beverage. Participants will only be enrolled in 1 of the 5 trials; as such, they will only consume the 1 plant-based alternative product in that trial.
Blood glucose
Blood glucose will be measured via finger-prick using a glucose meter at 0, 20, 35, 50, 65, 95, 125, and 145 minutes after treatment consumption.
Insulin
Insulin will be measured in the plasma through intravenous blood collection at 0, 35, 65, 95, 125, and 145 minutes after treatment consumption.
Glucagon-like Peptide-1 (GLP-1)
GLP-1 will be measured in the plasma through intravenous blood collection at 0, 35, 65, 95, 125, and 145 minutes after treatment consumption.
Glucagon-like Peptide-2 (GLP-2)
GLP-2 will be measured in the plasma through intravenous blood collection at 0, 35, 65, 95, 125, and 145 minutes after treatment consumption.
Gastric Inhibitory Polypeptide (GIP)
GIP will be measured in the plasma through intravenous blood collection at 0, 35, 65, 95, 125, and 145 minutes after treatment consumption.
Appetite
Appetite will be assessed through Adaptive Visual Analogue Scales (AVAS) questionnaires completed at 0, 20, 35, 50, 65, 95, 125 and 145 minutes after treatment consumption, and through an ad libitum pizza meal provided at 125 minutes post-treatment consumption, where participants will be instructed to eat until they are comfortably full over 20 minutes.
Click on the lead sponsor to view all of their trials.
