None listed
Conditions
Brief summary
Poor dietary patterns such as a high-calorie, high-fat (HCHF) diet can contribute to insulin resistance (IR), which is a condition where body does not respond to insulin as it should, and eventually lead to type 2 diabetes (T2D). Several human studies have confirmed that even 3-7 days of a HCHF diet impairs glucose metabolism, that is it impairs the ability of the body to remove glucose from the blood stream for energy storage and/or energy production. Our team has recently completed a human study (funded by Diabetes Australia, Ethics No: 2019-014) that showed 7-days of a HCHF diet in 14 healthy individuals led to increased meal-induced insulin concentrations within 3 days, followed by reduced meal-induced blood flow in the smallest capillaries of the muscle, also known as muscle microvascular blood flow after 7 days, compared to pre-intervention. However, the above-mentioned studies focused on saturated fat as their main source of fat. Whether the incorporation of high omega-3 polyunsaturated fats into a HCHF diet may protect against HCHF diet-induced hyperinsulinemia and impairments in skeletal muscle microvascular blood flow in healthy humans is not known and is the aim of the current study. We hypothesise that increasing omega-3 fat content in diet will protects against high fat diet-induced ‘early’ vascular impairments.
Interventions
High calorie, high fat feeding for 7 days in healthy people. This will include 50% higher energy intake than usual with energy 30% from carbohydrates, 50% from fat and 20% from Protein. The participants will be required to consume their usual diet plus the snacks provided by the investigatory team (including fish, nuts, sesame snaps, omega-3 enriched eggs). The dietary intervention will be overseen by the team dietitian. The participants will be required to record the snacks consumed each day on
High calorie, high fat feeding for 7 days in healthy people. This will include 50% higher energy intake than usual with energy 30% from carbohydrates, 50% from fat and 20% from Protein. The participants will be required to consume their usual diet plus the snacks provided by the investigatory team (including fish, nuts, sesame snaps, omega-3 enriched eggs). The dietary intervention will be overseen by the team dietitian. The participants will be required to record the snacks consumed each day on a checklist provided. The participants will also need to provide one day food diary before the pre and post fasting tests. Testing days in the lab will involve drinking a mixed meal drink (chocolate milk shake), providing blood samples and undergoing ultrasound scans. The mixed meal drink is 250ml milk shake that provides 1306.4kj energy (39.6g of carbohydrate, 20.6g of protein and 5.3g of fat).
Sponsors
Deakin university
Study design
Allocation
Non-randomised trial
Intervention model
Single group
Primary purpose
Prevention
Masking
Open (masking not used)
Eligibility
Sex/Gender
All
Age
18 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
Healthy males and females aged 18-45 years with a normal body mass index (BMI) [between 18 and 24.9 kg/m2, considered normal weight according to the World Health Organization]. Normotensive [seated brachial blood pressure less than 140/90 mmHg]. Have no dietary allergies or food intolerances. Have given signed informed consent to participate in the study.
Exclusion criteria
People who cannot read and communicate in English. People with any known food allergies. Regular smokers, or who have smoked in the past 10 years or/and smoked for more than 10 years will be excluded. History of severe liver disease, any vascular diseases or cardiovascular disease (previous stroke or heart attack), or T2D or who have a family history of T2D (parents with T2D). Pregnant or lactating women. People on a high fat diet (e.g. ketogenic diet) or a vegan/vegetarian diet. People consuming fish>2 times a week or take omega-3 supplements (supplementation for 2 or more days a week for more than a week, within the past 3 months). People exercising more than the current guidelines for physical activity (>5 hours of moderate intensity physical activity or > 2.5 hours of vigorous intensity physical activity per week).
Outcome results
None listed