Subjective Social Status and Energy Balance

Study Overview
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Brief Summary
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Investigators examined the associations between SSS, energy balance, food intake and changes in body composition following a high calorie lunch for 2 weeks.

Detailed Description
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Subjective social status (SSS) is inversely associated with body fatness. The physiological and psychological effects of low social status may spur increased energy intake as a strategy to buffer against future food scarcity. Investigators' central hypothesis is that females with low SSS will not compensate for excess calorie consumption in a single large meal as well as individuals with high SSS, and will therefore remain in positive energy balance leading to body fat gain in response to daily large meals. Investigators' objective is to understand the influence of SSS on eating behavior, weight gain, and energetic compensation. Investigators conducted a 14-day feeding protocol that consisted of consumption of a lunch-time meal that was 60% of participants' estimated 24-hour energy requirements each day in female participants between 20-50 years, with a body mass index between 25- 30 kg/m2. Free-living food intake was recorded using the Remote Food Photography Method outside of the lab on days 1-2 (early), 7-8 (middle), and 12-13 (late), to measure compensation in response to the large lunch. 24-Hour energy balance, 24 hour intake and post-lunch energy intake were calculated for those days. Investigators measured body composition using Dual energy x ray absorptiometry (DXA), weight and resting energy expenditure at the baseline and at the end of the 14 days of the intervention.

Official Title
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Perceived Social Status as a Determinant of Fat Accretion in Response to Excess Calories: the SSIB Study

Conditions
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Obesity, Social Dominance, Social Behavior, Eating Behavior

Intervention / Treatment
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* Behavioral: Dietary intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: between 20-50 years body mass index between 25- 30 kg/m2 Exclusion Criteria: food allergies or food restrictions engaged in any weight reduction program within the past 3 months experienced any weight loss or gain of >5% of body weight in the past 6 months for any reason except post-partum weight loss taking any medication that suppresses or stimulates appetite undergone prior surgical procedures for weight control or liposuction current smoker or has not smoked in less than 6 months any major diseases including active cancer or cancer requiring treatment in the past 2 years (except non-melanoma skin cancer) active or chronic infections (e.g., HIV or TB) cardiovascular disease or event including hospitalization or therapeutic procedures for treatment of heart disease in the past 6 months gastrointestinal disease kidney disease chronic obstructive airway disease requiring use of oxygen (e.g., emphysema or chronic bronchitis) diabetes (type 1 or 2) and taking any anti-diabetic medications and/or controlling the disease via dietary manipulations uncontrolled psychiatric disease a recent or ongoing problem with drug abuse or addiction consume more than three alcoholic drinks per day and has had 7 or more alcoholic beverages in a 24 hour period in the last 12 months pregnant or less than 3 months post-partum currently nursing or within 6 weeks of having completed nursing anticipating a possible pregnancy during the study

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Interventional Model Description: A prospective feeding study with convenience sampling
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Dietary intervention<br>All participants consumed a meal that contains 60% of their energy daily energy requirement as a lunch time meal for 14 consecutive days. | Behavioral: Dietary intervention<br>* For the feeding intervention, participants consumed a meal that contains 60% of their energy daily energy requirement as a lunch time meal for 14 consecutive days under observation except during the weekends. To ensure the participant receives 60% of the daily energy requirement as a lunch meal we added a supplemental shake to the standard 1200 kcal meal.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average 24 hour energy balance (24hr EB) | We measured 24-hr energy balance to assess the association of SSS with positive energy balance in response to a daily large meal perturbation. Twenty four hour energy balance was calculated for each time point as follows, and all six time points were averaged to get an average energy balance over the 2-week period: 24 hr Energy balance = Average 24 hr Energy intake / Resting Energy Expenditure *1.4 For the early and middle time point 24EB calculations, baseline resting energy expenditure (REE) was used and for late 24hr EB, final REE obtained at the end of the study was used. | Six time points ( Days 1, 2, 7, 8, 12 and 13) measured over the two week feeding protocol. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Average 24 hour energy intake (24hr EI) over a two week period | Amount of total calories consumed over 24 hours. - consists of breakfast, morning snack, lunch, afternoon snack, dinner, evening snack within 24 hours. | Average of six time points ( Days 1, 2, 7, 8, 12 and 13) over a two week period | 
| Post-lunch energy intake | Amount of total calories consumed after lunch - consists of afternoon snack, dinner, evening snack. | Average of six time points (Days 1, 2, 7, 8, 12 and 13) over a two week period | 
| Percent changes in body fat | Changes in the body fat mass | % change from baseline (day 0) to the end of the intervention period (day 14) | 
| Percent changes in body weight | Changes in the body weight | % change from baseline (day 0) to the end of the intervention period (day 14) | 
| Changes in adjusted resting energy expenditure | Resting energy expenditure (REE) was adjusted to the lean mass. the change in adjusted REE = final adjusted REE - baseline adjusted REE | change from baseline (day 0) to the end of the intervention period (day 14) | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Subjective social status, Obesity, High calorie intake, Energy balance, Eating behavior