None listed
Conditions
Brief summary
This study has been designed to investigate how isocaloric loads of protein (whey protein hydolysate), or fat (intralipid (10%)) differentially affect gastrointestinal motility, gastrointestinal hormone release, and appetite sensations in male individuals with a range of BMI (between 18-35 kg/m2). Further, the sensitivity of these individuals to the presence of protein or fat in the oral cavity will be measured and related to their gastrointestinal responsiveness to protein and fat, respectively. Relationships between BMI, gastrointestinal and oral sensitivities and habitual macronutrient and energy intake will also be assessed. Thus, the specific aims of this study are to determine: the effects of small intestinal lipid and protein, infused at a rate comparable to that of average gastric emptying, on antropyloroduodenal motility, gut hormone release, appetite and energy intake across a range of BMI oral fatty acid, and glutamate, sensitivity across a range of BMI And to assess the relationships between: oral sensitivity to oleic acid and glutamate and gastrointestinal responsiveness to fat and protein, respectively energy intake with oral taste sensitivity and/or gastrointestinal responsiveness, to fat and protein BMI with oral taste thresholds, and gastrointestinal sensitivity, to fat and protein habitual intake, BMI and oral and/or gastrointestinal sensitivity to fat and protein.
Interventions
The study requires 4 study visits, seperated by at least 3 days. Prior to each of the 4 study days, subjects will be provided with a McCains meat lasagne (400g, frozen) to consume for dinner the night before the study. Subjects will be asked to fast after this until arriving in the department.
On study days 1 and 2, subjects will recieve, in randomised, double-blinded fashion, a single 60 minute intraduodenal infusion at 4mL/min of either:
a) 3.0 kcal/min (Whey Protein Hydrolysate)
b) 3.0 kc
The study requires 4 study visits, seperated by at least 3 days. Prior to each of the 4 study days, subjects will be provided with a McCains meat lasagne (400g, frozen) to consume for dinner the night before the study. Subjects will be asked to fast after this until arriving in the department. On study days 1 and 2, subjects will recieve, in randomised, double-blinded fashion, a single 60 minute intraduodenal infusion at 4mL/min of either: a) 3.0 kcal/min (Whey Protein Hydrolysate) b) 3.0 kcal/min (10% Intralipid) Appetite sensation questionnaires in the form of a Visual Analogue Scale (VAS) will be administered and blood samples taken at t=-10 (prior to commencement of infusion- baseline), 0 (beginning of infusion) and throughout the infusion at t=15,30,45 and 60 min. A buffet meal will be provided at the end of infusion. The participant has 30 minutes to eat until comfortably full. The buffet meal consists of 300ml orange juice, 600ml water, 375ml iced coffee, 4 slices white bread, 4 slices brown bread, 100g deli leg ham, 100g virginian chicken, 4 slices cheese, 100g tomato, 100g cucumber, 100g lettuce, 2 portions mayonnaise, 2 portions margarine, 1 medium apple, 1 medium banana, 200g chocolate custard, 150g fruit salad, 200g strawberry yoghurt, and a 14g milky way chocolate bar. At t=90 min a final blood sample will be taken. Each volunteer will receive one of the two infusion solutions on two of four study days. Each infusion visit will be separated by no less than 3 days. Each infusion visit will last approximately 3-6 hours. On the remaining two study days (study visits 3 and 4) the volunteer will complete an oral sensitivity visit to establish at threshold concentrations at which oral cavity taste receptors are sensitive to: a) Oleic acid (fat) b) Mono-sodium glutamate (protein) Each oral sensitivity study day consists of an oral detection threshold task and a taste preference task, with the protein day also including a discrimination task. Each oral sensitivity visit will last approximately 2-3 hours. Subjects will be provided a meal at completion of the visit, which will not be assessed.
Sponsors
Dr Natalie Luscombe-Marsh
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used)
Eligibility
Sex/Gender
Male
Age
18 Years to 60 Years
Healthy volunteers
Yes
Inclusion criteria
Males with a BMI between 18-35 kg/m2. Weight stable (<5% fluctuation in body weight in previous 3 months).
Exclusion criteria
Significant gastrointestinal symptoms, disease, or surgery Use of prescribed or non-prescribed medications (including vitamins and herbal supplements) which may effect energy metabolism, gastrointestinal function, body weight, or appetite (eg. domperidone and cisapride, anticholinergic drugs (eg. atropine), metoclopramide, erythromycin, hyoscine, orlistat, green tea extracts, astragalus, St. johns wort etc.) Lactose intolerant or other food allergies (particularly MSG); intolerance or allergy to paracetamol Current, recurring or chronic rhinitis Current gallbladder or pancreatic disease; diabetes mellitus; epilepsy; cardiovascular or respiratory diseases; any other illnesses as assessed by the investigator (including chronic illnesses not explicitly listed above) Individuals with low ferritin levels or who have donated blood in the 12 weeks prior to taking part in the study Individuals with blood glucose and/or glycated haemoglobin outside the normal ranges. High performance athletes Current intake of >2 standard drinks on >5 days per week Current smokers of cigarettes/cigars/marijuana Current intake of any illicit substance Experience claustrophobia in confined spaces Unable to tolerate nasogastrointestinal tube, or to comprehend study protocol
Outcome results
None listed