None listed
Conditions
Brief summary
This study has been designed to investigate how the load of Whey Protein Hydolysate effects gut motility, gut hormones, and appetite sensations in obese individuals. Further, how response to a specific load of Whey Protein Hydolysate differs between obese and age-matched lean individuals will be investigated. There is evidence that protein more potently suppresses appetite and energy intake than carbohydrate and fat, however, the mechanisms behind this are not clear, and many studies show variable results due to differences in methodology. Our team has developed an intraduodenal infusion protocol appropriate to characterise the effects of varying protein loads in lean individuals on antropyloroduodenal motility, hormone release, and energy intake. Evidence suggests that normal hormone release and motility responses are perturbed in obese individuals. Thus, this study aims to characterise the effects of protein loads on gut motility, gut hormones, appetite sensations, and subsequent energy intake in obese individuals. We hypothesise that protein will modulate these parameters in a load-dependent manner, however, obese subjects will be less sensitive to loads of protein infused into the duodenum, compared to a healthy lean population. The results of this study may aid food and pharmaceutical industries in identifying appropriate responses to aid body weight management.
Interventions
A single 60 minute intraduodenal infusion at 4mL/min of
a) 0 kcal/min (saline control)
b) 1.5 kcal/min (Whey Protein Hydrolysate)
c) 3 kcal/min (Whey Protein Hydrolysate)
in 16 obese subjects
A single 60 minute intraduodenal infusion at 4mL/min of
a) 3 kcal/min (Whey Protein Hydrolysate)
in 16 lean subjects
Appetite sensation questionnaires in the form of a Visual Analogue Scale (VAS), blood samples.
A buffet meal will be provided at the end of the 60 minute infusion from which the volunteer
A single 60 minute intraduodenal infusion at 4mL/min of a) 0 kcal/min (saline control) b) 1.5 kcal/min (Whey Protein Hydrolysate) c) 3 kcal/min (Whey Protein Hydrolysate) in 16 obese subjects A single 60 minute intraduodenal infusion at 4mL/min of a) 3 kcal/min (Whey Protein Hydrolysate) in 16 lean subjects Appetite sensation questionnaires in the form of a Visual Analogue Scale (VAS), blood samples. A buffet meal will be provided at the end of the 60 minute infusion from which the volunteer 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 bar. Each obese volunteer will receive one of each infusion solution over three study days. Each study visit will be seperated by no less than 3 days. Each lean volunteer will receive the 3kcal/min infusion, requiring only 1 study visit. Each study visit will last approximately 3-6 hours.
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
No
Inclusion criteria
Obese with a Body Mass Index (BMI) of 30-35 kg/m2 and lean with a BMI of 18-25 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; intolerance or allergy to paracetomol Current gallbladder or pancreatic disease; diabetes mellitus; epilepsy; cardiovasculr 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 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 Restrained eaters (score >12 on the three factor eating questionnaire) Experience claustrophobia in confined spaces Unable to tolerate nasogastrointestinal tube, or to comprehend study protocol
Outcome results
None listed