None listed
Conditions
Brief summary
A comparison of mixed meals (smoothie compared to 'whole food') against the standard oral glucose tolerance test to investigate a) feasibility for use in assessing and monitoring metabolic response and b) use of c-peptide for assessing hyperinsulinaemia. Chronic hyperinsulinaemia associated with insulin resistance underpins many globally significant chronic diseases, including type 2 diabetes with resultant morbidity and premature mortality and economic burden. Although the relationship between elevated plasma glucose and /or insulin levels and chronic disease is accepted, there are mounting concerns about the methodologies used to diagnose these conditions. The globally standardised oral glucose tolerance challenge, the baseline measure for both glucose and insulin response tests, is standardised so that every adult older than 20 years receives 75g glucose, The fundamental flaw with this procedure is that glucose disposal rates vary depending on sex, lean body mass, physical activity and foods consumed during the previous 72 hours. Further criticisms of the oral glucose challenge include that it does not reflect normal eating patterns, and the excessively high glucose dose. It is hypothesised that a mixed meal tolerance test (a combination of protein, carbohydrate and fats) that is tailored to the participants’ gender, mass and activity status may provide a better platform from which to understand metabolic responses. It may also provide a better platform from which to better understand metabolic responses following dietary interventions to manage metabolic health, such as a low-carbohydrate diet. It is further hypothesised that c-peptide response patterns could be used as a proxy for insulin response patterns but comparative data is lacking. Recruiting 10 european males for a 3-way cross-over will collect sufficient data for this pilot.
Interventions
Observing the metabolic responses following each of three different meals: 75g glucose in 300mL water (using the commercial standard 'Carbotest' drink); mixed meal smoothie (SMMT) (e.g. milk, blueberries, banana, protein powder), and whole food mixed meal (WMMT) (e.g. muesli, milk and fruit with eggs on Vogel's toast). The latter two will be prepared for participants based on the information provided from a three-day food diary and will provide approximately one-third of their personalised dai
Observing the metabolic responses following each of three different meals: 75g glucose in 300mL water (using the commercial standard 'Carbotest' drink); mixed meal smoothie (SMMT) (e.g. milk, blueberries, banana, protein powder), and whole food mixed meal (WMMT) (e.g. muesli, milk and fruit with eggs on Vogel's toast). The latter two will be prepared for participants based on the information provided from a three-day food diary and will provide approximately one-third of their personalised daily caloric requirement. The carbohydrate, protein and total fat content of the smoothies and the mixed meals will comprise 55%, 20%, and 25%, respectively, of this energy intake. Foods used may vary slightly depending on caloric requirements. It is typical, and will be encouraged, for the glucose drink to be consumed within about 5 minutes. Participants will be timed eating the SMMT and WMMT. Ideally these meals will be consumed within 15 minutes. It is anticipated that each test will take 3-3.5 hours to complete. (e.g. three hours from the commencement of the meal, but allow about 30 minutes for administration and initial cannulation) Each test will be conducted seven days apart to allow a 'wash-out' between each testing period.
Sponsors
Auckland Universityof technology
Study design
Allocation
Randomised controlled trial
Intervention model
Crossover
Primary purpose
Diagnosis
Masking
Open (masking not used)
Eligibility
Sex/Gender
Male
Age
20 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
NZ European Healthy with no recent injuries (acute or chronic) Currently consuming at least 150g carbohydrate per day for at least two weeks prior to the testing period. Able to provide informed consent and adhere to research protocols.
Exclusion criteria
Body mass index less than 18 kg/m2 Any food allergy or intolerance, including, but not limited to coeliac disease, lactose intolerance, and nut or egg allergies. An unwillingness to consume a variety of foods, even in the absence of food allergies or intolerances. Anyone with a medical condition (illness or injury) that may cause: increased bleeding, poor circulation, poor venous access, or unstable health. Anyone with a known gastrointestinal disorder, including, but not limited to, inflammatory bowel disease, irritable bowel disease, chronic constipation or diarrhoea, or recent (within 4 weeks) gastrointestinal infection. Anyone taking medication that can affect blood glucose, phosphate, or lipid levels including (but not limited to): insulin; sulphonylurea medications; metformin; statins; or calcium. A history of cancer (excluding non-melanoma skin cancers). Current smokers / vapers or those recently discontinued smoking/vaping (previous three months).
Outcome results
None listed