None listed
Conditions
Brief summary
1. Hypothesis We hypothesise that red and processed meat and refined grains negatively affect insulin sensitivity or insulin secretion, compared with dairy products, legumes, nuts and whole grains. 2.Aims If a dietary pattern rich in nuts, legumes, whole grains and dairy products improves insulin sensitivity, this study will strongly support the recommendation of this diet for people with no diabetes. If a dietary pattern high in red, processed meat and refined grains affects negatively insulin sensitivity, this outcome will provide a convincing rationale in reducing the amount of intake of red, processed meat and refined grains for those with insulin resistance. This study will provide clarification on dietary influences on insulin sensitivity and contribute to lowering risks of developing type 2 diabetes by changing the dietary patterns. 3. Primary and secondary endpoints The primary endpoint of this study is to assess insulin sensitivity and the secondary endpoint is to analyse the biomarkers of insulin resistance.
Interventions
This study is a randomized cross-over trial with two different diets: one is a dietary pattern with high red meat and processed meat and refined grains and the other with legumes, nuts, whole grains and dairy products. This study will run for at least 10 weeks and 2 days with 8 visits. The intervention will consist of two 4 week weight stable diet periods with a minimum of 2-week washout period on a usual diet in between.
Participants will be asked to fill out a 3-day weighed food record every 2
This study is a randomized cross-over trial with two different diets: one is a dietary pattern with high red meat and processed meat and refined grains and the other with legumes, nuts, whole grains and dairy products. This study will run for at least 10 weeks and 2 days with 8 visits. The intervention will consist of two 4 week weight stable diet periods with a minimum of 2-week washout period on a usual diet in between. Participants will be asked to fill out a 3-day weighed food record every 2 weeks and daily checklists with food consumed. Participants will be asked to follow specific instructions on diet. The two diets will be designed for individuals depending on their weight and activity levels. The dietary design of this project has been virtually run by foodworks 7 based on Australian dietary habits. The dietary cluster with red and processed meat and refined grains includes 200-300g red meat, more than 50g processed meat (ham, bacon and sausage) and 4-6 serves refined grains (bread, rice, noodle and pasta) based on volunteers’ weights. One to two serves vegetables/day, 1-2 serves fruits/day and a minimal amount of dairy products (e.g. 1-2 teaspoons of milk). Two hundred to three hundred gram of potatoes, 1 serve of jam or marmalade, 3-9 serves of oil or spread, and 3-4 serves of indulgence food (in place of refined grains or potato) were recommended for additional energy intake in accordance with volunteers’ weights. In the dietary cluster high in nuts, legumes, whole grains and dairy products, participants will consume 4 serves of dairy products/day, 60-90 g unsalted nuts/day, 3-4 serves whole grains/day in the forms of breads, rice and pasta, 1-2serves fruits and 1-2 serves vegetables/day. 70-150 g chicken or fish (or other seafood) or 150-225 g cooked legumes based on the volunteers’ weight will be eaten alternatively each day. Two to seven serves of oil or spread and 1 serve of jam or marmalade were advised for additional energy intake in accordance with volunteers’ weights. Participants will be provided with kitchen scales. Participants will be asked to submit a 3-day weighed food record and daily checklists at visit 2, 3, 6 and 7. Participants will be required to have a 12 hour fast before each visit. Weight measurement and blood sampling will be performed during the course of this study. Blood samplings by MTT (meal tolerance test) and LDIGIT (low dose insulin and glucose infusion test) will be performed at the end of each diet. In terms of MTT, participants will be asked to consume a sandwich within 10 min. Blood samples will be taken at -5, 0, 10, 20, 30, 40, 50, 60, 75, 90, 120, 150, and 180 min. On the other day, LDIGIT will be administered over 150 min after a 12h overnight fast. 19 blood samples will be collected over 150 min. Blood samples will be retained for measurements of insulin, C-peptide and glucose.
Sponsors
University of south Australia
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Treatment
Masking
Blinded (masking used) (Investigator)
Eligibility
Sex/Gender
All
Age
18 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
1. People in BMI ranges of 18.50 to 45 2. Aged over 18 years 3. Normal glucose tolerance or impaired glucose tolerance
Exclusion criteria
1.Diagnosed diabetes 2.Drugs that influence glucose metabolism (e.g. Metformin) 3.Pregnant or breastfeeding 4.History of metabolic illness such as kidney or liver diseases
Outcome results
None listed