None listed
Conditions
Brief summary
This study has been designed to investigate how a high-protein or high-fat preload effect thermogenesis, antropyloroduodenal motility, gut hormones, gastric emptying and appetie. Volunteers are required to visit the department on 3 occasions (6 if they wish to take part in Study 2 as well) approximately 7 days apart. They will be required to injest one of the three preloads on each occassions, and lie supine under a calorimetry hood. Venous blood samples will be taken at set intervals and appetite questionnaire will be answered after a blood sample has been collected. A buffet meal will be presented at 180min and consumed over 30 minutes until comfortably full.
Interventions
3 semi-solid preloads with the following compositions will be tested: 1. Control (low energy, % energy as protein/carbohydrate/fat is 12/32/54); 2. High-protein (HP) 55/30/15); and 3. high-fat (HF) (15/30/55). Whey protein and cream will be used for HP and HF preloads, respectively.
Study 1:
Fasting and posprandial energy expenditure, appetite profile, gastric emptying , gut hormone release and subsequent energy intake will be measured.
Fasting and postprandial energy expenditure will be mea
3 semi-solid preloads with the following compositions will be tested: 1. Control (low energy, % energy as protein/carbohydrate/fat is 12/32/54); 2. High-protein (HP) 55/30/15); and 3. high-fat (HF) (15/30/55). Whey protein and cream will be used for HP and HF preloads, respectively. Study 1: Fasting and posprandial energy expenditure, appetite profile, gastric emptying , gut hormone release and subsequent energy intake will be measured. Fasting and postprandial energy expenditure will be measured by indirect calorimetry using a clear plastic ventilated hood and the TrueOne metabolic monitor. Appetite profile will be measured using a Visual Analogue Scale (VAS) and gut hormones by blood samples. Gastric emptying will be measured indirectly using 20mg/kg paracetamol dissolved in 100mL of preprepared low-joule lemon cordial. Energy intake will be assesed by weighing food presented to the volunteer before and after consumption. The buffet meal will 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 lettuce, 100g cucumber, 100g tomato, 2 portions mayonnaise, 2 portions margarine, 1 medium apples, 1 medium banana, 200g chocolate custard, 150g fruit salad, and 200g strawberry yoghurt. The volunteer will be given 30 minutes to eat until he/she is comfortably full. The volunteer will recieve one of the three preloads on each of the three study days. Each study day will be seperated by approximately one week. Study 2: Antropyloroduodenal activity will be assessed using a 3.5mm wide manometric catheter. The catheter will be inserted through an anaethetised nostril and allowed to pass by peristalsis through the pylorus into the duodenum. Antropyloroduodenal pressures will be continously recorded and the number of antral, duodenal and isolated pyloric pressure waves, and basal pyloric pressure waves will be calculated. Volunteers will be enrolled in study 1 and if they wish, they can also participate in study 2 however, study 2 is not compulsory. Both studies are a cross over design. Each participant in each study will consume of the three preloads, in random order.
Sponsors
Professor Christine Feinle-Bisset
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
No
Inclusion criteria
16 overweight/obese (BMI 27-35kg/m2) subjects will be recruited. All subjects will be required to be weight-stable (i.e. <5% fluctuation in their body weight) at study entry. Subjects will be requried to maintain their normal physical activity over the course of the study.
Exclusion criteria
Significant gastrointestinal symptoms, disease or surgery, use pf prescription or non-prescription medications (including vitamins and herbal suppliments) which may affect energy metabolism, gastrointestinal function, body weight or appetite (eg. domperidone and cisapride, anticholinergic drugs (ag. atropine), metoclopramide, erythromycin, hyoscine, orlistat, geren tea extracts, Astragalus, St Johns Wort etc), intolerance /allergy to paracetamol, current gallbladder or pancreatic disease, diabetes mellitus, epilepsy, cardiovascular or respiratory disease, any other illness as assessed by the investigator (including chronic illnesses not explicitly listed above), high performance athletes, current intake of >2 standard drinks on >5 days per week, curent smokers of cigarettes/cigars/marijuana, current intake of any illicit substances, restrained eaters (score > 12 on the three factor eating questionnaire), experience claustrophobis in confined spaces, or unable to comprehend the study protocol.
Outcome results
None listed