Insulin Sensitivity
Conditions
Brief summary
The hypothesis is that consumption of pulse-based foods (i.e. containing chickpeas, lentils, and split peas) during the workday will improve insulin sensitivity, glucose tolerance, blood lipids, body composition, and blood pressure in sedentary office workers.One-hundred office workers from a university campus will participate in a cross-over study where they will be randomized (i.e. assigned by chance) to receive pre-packaged pulse-based lunches and snacks to replace their usual lunches/snacks during the work day OR to continue consuming their usual diets for two months. After the first dietary intervention, they will undergo a 1-month wash-out and then participate in two months of the opposite dietary intervention. The main outcome to be assessed is change in glucose and insulin (i.e. blood sugar control) determined during an oral glucose tolerance test. Secondary outcomes include changes in body composition, lipids, and blood pressure. During the pulse-based diet phases, participants will be supplied with a ready-to-eat lunch and two snacks to eat during each workday. These will contain a total of 150g/d dry weight (250g/d wet weight) pulses
Detailed description
Sedentary behaviour has been deemed the new smoking based on multiple and potent negative impacts on health. Moreover, sedentary behaviour is a strong predictor of type 2 diabetes risk and cardiovascular disease. Previous studies have show that pulse-based meals derived from lentils, beans, chickpeas, and peas are effective for alleviating risk factors associated with diabetes and cardiovascular disease in clinical populations including older adults, overweight and obese individuals, and women with polycystic ovary syndrome; however, to date, there have been no nutrition-based interventions for alleviating risk factors for diabetes specifically targeting office workers exposed to long periods of sitting. Although people are aware of the health benefits of pulses, a major barrier to increased consumption continues to be a lack of knowledge on how to prepare pulse-based meals. This proposed study is designed to overcome this barrier. The main goal of this research study is to determine whether improvements in cardio-metabolic health can be realized by giving people pulse-based lunches and snacks to replace their regular workplace lunches and snacks. In this randomized controlled trial, 100 office workers from the University of Saskatchewan will participate in a cross-over study where they will be randomized into one of two diets for 2 months: Receive pre-packaged pulse-based lunches and snacks to replace their usual lunches/snacks during the work day OR to continue consuming their usual diets for two months. After a one-month washout, they will cross-over to the other condition. The primary outcome measure, Matsuda Index (determined by blood glucose and insulin responses to an oral glucose tolerance test), will be assessed before each diet phase and at the end (i.e. two months) of each diet phase. Secondary outcome measures (body composition, waist girth, lipids, blood pressure will also be assessed.
Interventions
DIETARY_SUPPLEMENTPulse-based diet
Low Glycemic Index
DIETARY_SUPPLEMENTRegular diet
Moderate Glycemic Index
Sponsors
University of Saskatchewan
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
DOUBLE (Investigator, Outcomes Assessor)
Intervention model description
Crossover: 1. Pulse-based diet; 2. Regular diet
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
* Men and Women * 18y or older * Engaged in \>5 hours per day sitting
Exclusion criteria
* Diagnosed with diabetes * taking glucose or lipid-lowering medication * Regular consumers of pulses (1.5 cups (250g) or greater of pulses per week) * Engaged in 60 minutes or greater of physical activity per day
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Insulin sensitivity | Change from baseline to 8 weeks | Matsuda Index determined by glucose and insulin response to oral glucose tolerance test |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Insulin area under the curve | Change from baseline to 8 weeks | Insulin area under the curve from a 2-hour oral glucose tolerance test |
| Fasting glucose | Change from baseline to 8 weeks | Fasting glucose |
| Fasting insulin | Change from baseline to 8 weeks | Fasting insulin |
| Low-density lipoprotein cholesterol | Change from baseline to 8 weeks | LDL-C from fasting blood samples |
| High-density lipoprotein cholesterol | Change from baseline to 8 weeks | HDL-C from fasting blood samples |
| Total cholesterol | Change from baseline to 8 weeks. | Total cholesterol from fasting blood samples |
| Glucose area under the curve | Change from baseline to 8 weeks | Glucose area under the curve from a 2-hour oral glucose tolerance test |
| Waist Girth | Change from baseline to 8 weeks | Waist Girth |
| Fat mass | Change from baseline to 8 weeks | Fat mass from DXA measurements |
| Lean tissue mass | Change from baseline to 8 weeks | Lean tissue mass from DXA measurements |
| Systolic blood pressure | Change from baseline to 8 weeks | Systolic blood pressure measured at rest |
| Diastolic blood pressure | Change from baseline to 8 weeks | Diastolic blood pressure measured at rest |
| Triglycerides | Change from baseline to 8 weeks | Triglycerides from fasting blood samples |
Countries
Canada
Outcome results
None listed