Calcium, Protein and Gut Hormones

Not Applicable

Completed

Interventions: Dietary Supplement: Calcium Citrate
Dietary Supplement: Milk Mineral Supplement
Dietary Supplement: Whey Protein Hydrolysate

Brief Summary: Gut hormones have therapeutic potential in the prevention and treatment obesity and type 2 diabetes (T2D). Milk protein and calcium can each potentiate gut hormones following meal ingestion in humans. However, these nutrients may interact synergistically (and with other minerals in milk) such that specific co-ingestion of these nutrients is required to obtain the full therapeutic potential for metabolism and energy balance. This proposal is to perform a pilot study on the effect of co-ingesting Capolac® plus protein on circulating gut hormone responses.

Detailed Description: Participants will be asked to arrive to the laboratory between 08:00 and 10:00 am after not eating for between 8-14 hours i.e. in a fasted state (water intake is permitted and encouraged). Participants will then be given one of three test drinks: 1) calcium citrate (1000 mg); 2) milk mineral supplement (equating to 1000 mg calcium); or 3) milk mineral supplement (equating to 1000 mg calcium) plus whey protein hydrolysate (50 g). Each of these drinks will also contain 500 mL of water and artificial sweetener (80 mg sucralose).

Blood samples will be taken before, and at 15, 30, 45, 60, 90 and 120 minutes after ingestion of the test drink to determine the concentrations of gut hormones (GIP, GLP-1 and PYY) circulating in the bloodstream. We will also ask participants to complete an appetite questionnaire at baseline and every 30 minutes after ingestion of the test drink to assess their appetite sensations. After the 120-minute time point, we will remove the cannula and the trial day will be complete.

Recruitment & Eligibility

Inclusion Criteria

Exclusion Criteria

Any previous or current metabolic, cardio-pulmonary or musculoskeletal disease
Not between the ages of 18-65 years
A body mass index below 18.5 kg/m2 or above 30 kg/m2 (body mass (kg) divided by your height (m) squared)
Taking medications that may influence your metabolism
Plans to change your lifestyle (diet and/or physical activity) during the study period
Not willing to refrain from alcohol containing drinks or unaccustomed exercise one day before the laboratory sessions.
Current smoker

Arm && Interventions

Group	Intervention	Description
Calcium Citrate	Calcium Citrate	Calcium citrate (1000 mg calcium) will be consumed by participants in the morning between 8-10 am after 8-14 h fasting. Blood samples, appetite scales and expired breath samples will be taken in a regular intervals for 2 h after ingestion.
Milk mineral supplement plus Whey Protein Hydrolysate	Whey Protein Hydrolysate	Milk mineral supplement (equating to 1000 mg calcium) plus whey protein hydrolysate (50 g) will be consumed by participants in the morning between 8-10 am after 8-14 h fasting. Blood samples, appetite scales and expired breath samples will be taken in a regular intervals for 2 h after ingestion.
Milk Mineral Supplement	Milk Mineral Supplement	Milk mineral supplement (equating to 1000 mg calcium) will be consumed by participants in the morning between 8-10 am after 8-14 h fasting. Blood samples, appetite scales and expired breath samples will be taken in a regular intervals for 2 h after ingestion.
Milk mineral supplement plus Whey Protein Hydrolysate	Milk Mineral Supplement	Milk mineral supplement (equating to 1000 mg calcium) plus whey protein hydrolysate (50 g) will be consumed by participants in the morning between 8-10 am after 8-14 h fasting. Blood samples, appetite scales and expired breath samples will be taken in a regular intervals for 2 h after ingestion.

Primary Outcome Measures

Name	Time	Method
Postprandial plasma GLP-1 area under the curve (mmol/L x 120 min).	120 min	Plasma glucagon-like peptide-1 (GLP-1) concentrations

Secondary Outcome Measures

Name	Time	Method
Postprandial plasma GIP area under the curve (mmol/L x 120 min)	120 min	Plasma glucose-dependent insulinotropic peptide (GIP) concentrations
Postprandial plasma PYY area under the curve (mmol/L x 120 min)	120 min	Plasma peptide tyrosine tyrosine (PYY) concentrations.
Energy metabolism (carbohydrate and fat oxidation)	120 min	Carbohydrate and fat oxidation (g/h) measured via indirect calorimetry
Postprandial plasma glucose	120 min	Plasma glucose concentrations (mmol/L).
Blood pressure	120 min	Systolic and diastolic blood pressure
Subjective ratings of appetite (au)	120 min	Visual analogue scales of appetite ratings