Impact of Different Rates of Weight Loss on Final Outcomes in Pre-menopausal Women
Trial Snapshot
- Phase
- Not Applicable
- Status
- Completed
- Sponsor
- University of Ottawa
- Enrollment
- 30
- Primary Endpoint
- Change in Resting energy expenditure after weight loss
Study Overview
Brief Summary
The study will include 30 women randomized in two distinct groups: G1: Slow weight loss and G2: Rapid weight loss . The total duration of the program will be different for each group, being over 20 and 10 weeks for G1 and G2, respectively, in attempt to match the groups on amount of weight loss (approximately 20 pounds per subject). Participants who meet the inclusion criteria will be randomized to rapid or slow weight loss groups. The energy deprivation of the rapid and slow weight loss will be in -1000 kcal/day and -500 kcal/day, respectively. Calculated based on the baseline resting energy expenditure (REE; determined by indirect calorimetry) and their physical activity level measured for one week. The diet macronutrient composition will be personalized for each participant based on the results of 2-day energy intake at preliminary session, measured with food items selected from a validated food menu. Individuals will be instructed to maintain the level of energy restriction and macronutrient composition during the diet period, however they will be able to do food exchanges, based on the Canadian Diabetes Association system. It will be measured participant's body weight, body compositions, appetite sensations, resting energy expenditure, energy intake, palatability, olfactory performance, food reward, food reinforcement and impulsivity. Participants will have 7 sessions in total: 1 preliminary, baseline, 7 days of intervention, 3 follow ups and final assessment.
Detailed Description
Preliminary session (approximately 3 hours) During this visit, participants will receive the consent form and they will be informed of the experimental procedures, which will be used during each experimental session, as well as the equipment that will be used to obtain the necessary data. Their weight (digital scale), height (standard stadiometer), waist circumference and blood pressure will be measured at the start the session. If participants match the study inclusion criteria, they will have an equal chance of being assigned to one of two groups; one intervention will last 10 weeks and the second intervention will last 20 weeks but both groups are designed to produce the same amount of weight loss. We will measure their resting metabolism (the energy you use while at rest) (indirect calorimetry). We will then serve a breakfast according to their personal choice and we will recommend them to "eat as much or as little as they want" in 15 minutes. Then, they will be asked to complete other questionnaires the Yale Food Addition Questionnaire that measure personality traits and food addiction symptoms, respectively. This session will be used to determine their breakfast during the experimental sessions and to determine the macronutrient composition (percentage of carbohydrates, fat and protein) will be adopted for them during their diet. They will be asked to fill a food menu and choose your meals for the rest of your day as well as for the day that will follow their visit. We will provide all your food items in lunch boxes and individual bags. They will be able to carry these items and they will be instructed to eat only the items that they have chosen for these 2 days. Lastly, they will be asked to wear a biaxial accelerometer around your upper arm, 24 hours per day during 7 days, including when sleeping, but should remove it when in contact with water (for instance, when bathing, showering or swimming) because this device is not waterproof.
Second Visit: (approximately 1 hour) Upon completion of the preliminary phase, participants will be invited to a 2nd meeting at the lab, in order to receive the dietary instructions related to their weight loss program. This diet is the one that you will be instructed to follow for the duration of the weight loss program (10 or 20 weeks depending on their group). The diet will be prescribed using the Canadian Food Exchange System. This method will allow you to select foods you enjoy during the weight loss, however in smaller quantities.
Exchange lists are groups of foods that contain a similar mix of carbohydrates, protein, fat, and calories. The Canadian exchange system there are seven exchange groups: Grains & Starches; Fruits; Milk & Alternatives; Vegetables; Meat & Alternatives; Fats; Unlimited consumption.
Within any group, participants can exchange one food serving for another. For example, in the Meats group, some sample foods that equal one lean meat exchange might be: 1 oz. of white meat chicken or turkey with no skin or 1 oz. of lean beef.
The daily meal plan will contain foods from all seven Food Exchange lists in order to assure them a complete and a balanced nutrition. However, the number of portions from each group will be recommended based on their individual diet evaluated in the preliminary session. This session will also be used to clarify any potential questions that participants have regarding the project and the intervention.
Study Design
- Study Type
- Interventional
- Allocation
- Randomized
- Intervention Model
- Parallel
- Primary Purpose
- Treatment
- Masking
- None
Eligibility Criteria
- Ages
- 20 Years to 55 Years (Adult)
- Sex
- Female
- Accepts Healthy Volunteers
- Yes
Inclusion Criteria
- •Present a 30≥BMI≥40 kg/m2,
- •Present a waist circumference >88 cm
- •Must be weight-stable (±2 kg last 6 months)
- •Must be sedentary (less than 150 minutes per week)
- •Must be able to read in English
- •Must to present no history of alcohol or drugs abuse
- •Must be pre-menopausal with a regular menstrual cycle
Exclusion Criteria
- •present scores >12 in the 16-item Binge Score Symptoms and/or score >19 in the Depression Beck Inventory
- •present any history or evidence of cardiovascular disease, peripheral vascular disease, or stroke;
- •be insulin dependent (75g oral glucose tolerance test)
- •present a known renal and/or liver disease
- •present asthma requiring therapy
- •present plasma cholesterol > 8 mmol/L
- •present systolic blood pressure > 140 mmHg or diastolic blood pressure > 90 mmHg
- •present previous history of inflammation disease, or cancer,
- •present untreated thyroid or pituitary disease
- •consume regularly medications that could affect cardiovascular function and/or metabolism
- •present food allergies
- •be pregnant
- •be smoker
Outcomes
Primary Outcomes
Change in Resting energy expenditure after weight loss
Time Frame: 20 weeks
Resting energy expenditure will be measured at baseline and in the end of the intervention
Secondary Outcomes
- changes in Food reward using the LFPQ after weight loss(20 weeks)
- changes in food reinforcement for favourite fruit using a Behavioural choice computer task(10 weeks)
- changes in food reinforcement for favourite fruit using a Behavioural computer choice task(20 weeks)
- changes in food reinforcement for favourite snack using a Behavioural choice task(10 weeks)
- changes in impulsivity using the Barrat Impulsiveness scale after weight loss(20 weeks)
- changes in food reinforcement for favourite snack using a Behavioural choice computer task(20 weeks)
- changes in olfaction using the 'Sniffin Sticks' tests(20 weeks)
- Change in fasting Appetite sensations using a Visual Analogue scale after weight loss(10 weeks)
- Change in post-prandial Appetite sensations using a visual Analogue scale after weight loss(20 weeks)
Investigators
Eric Doucet
Professor
University of Ottawa