Multi-level Supermarket Discount Study

Not Applicable

Completed

Brief Summary: The study team's objective is to test the effect of supermarket discount levels on fruit and vegetable (F\&V) and non-caloric beverage purchasing and consumption, as well as health outcomes. The study team will implement this economic intervention in a local supermarket chain to assess the effects of a 32-week intervention of fruit and vegetable (F\&V) and non-caloric beverage discounts of 30%, 15%, and 0% (control group) on purchasing, dietary intake, and health outcomes, including body weight and composition, blood pressure, and biochemical markers of cardiovascular disease risk. The 32-week intervention will be preceded by an 8-week baseline and will have a follow-up period of 16 weeks. There will be no discounts in effect during the baseline and follow-up periods.

Detailed Description: The objective is to test the effect of supermarket discount levels on fruit and vegetable (F\&V) and non-caloric beverage purchasing and consumption, as well as health outcomes. The study team will implement this economic intervention in a local supermarket chain to assess the effects of a 32-week intervention of fruit and vegetable (F\&V) and non-caloric beverage discounts of 30%, 15%, and 0% (control group) on purchasing, dietary intake, and health outcomes, including body weight and composition, blood pressure, and biochemical markers of cardiovascular disease risk. The prediction is that the impact will increase with the level of discount. The 32-week intervention will be preceded by an 8-week baseline and will have a follow-up period of 16 weeks. There will be no discounts in effect during the baseline and follow-up periods. The prediction is that some of the interventional effects will carry over to the follow-up period.

Recruitment & Eligibility

Inclusion Criteria

BMI: 24.5 - 50
Weight Stable (±5% body weight in last 3 mo)
Accessible by telephone
Living in NYC and not planning move
Primary household food shopper
≥50% of food shopping at Foodtown/Brooklyn Harvest and agrees to 100% shopping at store during study
Consumption of >50% of food shopping
Eat out or take out ≤5 times weekly

Exclusion Criteria

Pregnant or contemplating pregnancy
Enrolled in related studies
Active weight loss program
Presence of serious medical (e.g. cancer, diabetes) or psychiatric disease (e.g. bipolar)
Changes in medications or smoking in past 3 mo
Excessive alcohol use (≥4 drinks/day) or illicit drug use
Planning a vacation ≥ 4 consecutive weeks or 6 total weeks during study
Receiving SNAP benefits

Arm && Interventions

Group	Intervention	Description
Experimental 30% discount intervention	Discount Intervention	30% discount on fruits, vegetables and non-caloric beverages at the designated supermarkets
Experimental 15% discount intervention	Discount Intervention	15% discount on fruits, vegetables and non-caloric beverages at the designated supermarkets

Primary Outcome Measures

Name	Time	Method
Fruit Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: Fruit intake as assessed by 24-h dietary recalls
Vegetable Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: Vegetable intake as assessed by 24-h dietary recalls
Bottled Water Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: bottled water intake as assessed by 24-h dietary recalls
Seltzer Water Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: seltzer water intake as assessed by 24-h dietary recalls
Diet Soda Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: diet soda intake as assessed by 24-h dietary recalls
Total Non-caloric Beverage Intake as Assessed by 24-h Dietary Recalls	Week 8, 24, 40, 56	Individual consumption behaviors: Total non-caloric beverage intake as assessed by 24-h dietary recalls

Secondary Outcome Measures

Name	Time	Method
Body Weight	Week 0, 8, 24, 40, 56	Body weight (kg)
Body Mass Index (BMI)	Week 0, 8, 24, 40, 56	BMI (kg/m\^2)
Percent Body Fat	Week 0, 8, 24, 40, 56	% body fat
Waist Circumference	Week 0, 8, 24, 40, 56	Waist circumference (cm)
Fasting Glucose	Week 0, 8, 24, 40, 56	Fasting glucose level
Cholesterol Level	Week 0, 8, 24, 40, 56	Cholesterol level
Blood Pressure	Week 0, 8, 24, 40, 56	Blood pressure systolic and diastolic.
Gross Weekly Purchasing of Fruits and Vegetables	Week 8-56	Gross weekly purchasing of fruits and vegetables from the discounted items list in dollars