Obesity, PreDiabetes
Conditions
Keywords
weight loss, reduced carbohydrate diet, exercise training, time restricted eating
Brief summary
This 16-week study will use an experimental approach called the Sequential Multiple Assignment Randomized Trial to help determine which combination and sequence of weight loss program features are most effective in people who are at risk for type 2 diabetes. Participants in the study will be initially randomized to consume either a high or reduced carbohydrate diet. After 4 weeks, participants will be identified as Responders (greater than or equal to 2.5% weight loss) or Non-Responders (less than 2.5% weight loss). Responders will continue with their initial randomized group for the remainder of the trial. Non-responders will be re-randomized to 2nd stage interventions of either including additional exercise counseling and training or beginning a time restricted eating protocol for the remainder of the trial.
Interventions
BEHAVIORALHigh Carbohydrate Diet
Participants randomized to this group will participate in a group-based weight behavioral management program and consume a high carbohydrate (HC) diet. Because this protocol uses a sequential, multiple assignment, randomized trial (SMART) design, response will be assessed at week 4. Responders will continue with their 1st stage assignment for the remainder of the study. Non-responders will be randomized to 2nd stage intervention of either combine HC diet with time-restricted eating (TRE) or HC diet with additional exercise counseling and support.
BEHAVIORALReduced Carbohydrate Diet
Participants randomized to this group will participate in a group-based behavioral weight management program and consume a reduced carbohydrate (RC) diet. Because this is a sequential, multiple assignment, randomized trial (SMART) design, response will be assessed at week 4. Responders will continue with their 1st stage assignment for the remainder of the study. Non-responders will be randomized to 2nd stage intervention of either combine RC diet with time-restricted eating (TRE) or RC diet with additional exercise counseling and support.
Sponsors
General Mills
University of Alabama at Birmingham
Study design
Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
PREVENTION
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
18 Years to 75 Years
Healthy volunteers
Yes
Inclusion criteria
* 18-75 years of age * BMI of 27 kg/m2 or greater * at risk for developing type 2 diabetes (prediabetes)
Exclusion criteria
* Pregnant, planning to become pregnant, or breastfeeding * uncontrolled hypo or hyperthyroidism
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Changes in body weight | week 16 visit | Measured on digital scale at final visit. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in glucose | week 16 visit | Serum glucose will be measured in a fasted state. |
| Change in hemoglobin A1c | week 16 visit | A1c is a measure of average glucose over the previous 3 months. |
| Change in insulin | week 16 visit | Serum insulin will be measured in a fasted state. |
| Changes in QUICKI index | week 16 visit | Predictor of insulin resistance that will be calculated from glucose and insulin measures |
Other
| Measure | Time frame | Description |
|---|---|---|
| Changes in overall strength | week 16 visit | As measured by hand grip dynamometry |
| Changes in fat mass | week 16 visit | As measured by bioelectrical impedance analysis (BIA) on the InBody S10 body composition analyzer. |
| Diet Intake and Physical Activity Monitoring | week 16 visit | 7-day food logs and weekly physical activity logs |
| Changes in lipids | week 16 visit | Fasting serum concentrations of total cholesterol, HDL cholesterol, triglycerides, and LDL cholesterol |
| Change in Blood Pressure | week 16 visit | Measured with a clinical grade blood pressure cuff. |
| Changes in body weight | week 4 visit | Measured on digital scale in order to determine responder or non-responder status. |
| Changes in aerobic fitness | week 16 visit | As measured by the 3-minute step test. |
Countries
United States
Outcome results
None listed