Front of Pack Nutritional Labeling of Processed Foods Among Mexican Consumers

Study Overview
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Brief Summary
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The effect of three front of pack (FOP) labeling schemes (Mexican Guideline Daily Amounts (GDA), Ecuador's Multiple Traffic Light (MTL) and Chilean Warning Labels (WL) in red) on purchasing intentions was evaluated using a randomized experiment of an online shopping simulation. The study employed an online grocery store developed for this purpose to simulate a shopping situation.

Detailed Description
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Nutrition labels may modify purchasing behavior. Different labels may influence consumer purchasing behaviors in different ways. In general, for nutrition labels to have any effect on purchasing decisions, consumers must first be exposed to them and perceive the displayed information on the labels. Then, the effect will be mediated by consumer understanding. Based on this understanding, consumers may use the label to make inferences about the nutritional quality or healthiness of the product, which, together with other information (e.g. trust or liking of the label or taste of the product) may affect the evaluation of the product and eventually the purchase decision of the product. GDA provide numeric information on the content of key nutrients in the food product without interpreting the information. MTL and WL are nutrient-specific labels providing an interpretation of the nutritional content of specific nutrients in the product. The MTL uses traffic light colors to indicate the high (red) or low (green) content of key nutrients, whereas the WL are only included in a product when the content of each key ingredient is above specific criteria. Trained undergraduate student research assistants from eight universities across the country recruited the study participants. Research assistants were trained on how to approach and recruit participants and obtain informed consent. They were instructed to recruit 20 or more participants each. Recruitment took place in public spaces previously selected by convenience by the research team, based on their use by low- and middle-income groups in Mexico (i.e., public schools, public squares, public health centers, as well as supermarket chains and shopping centers located in low-income neighborhoods). Potential participants were approached by research assistants, who explained study objectives and invited them to be part of the study. Then, individuals were screened for eligibility using a 3-item screener. To access this screener, research assistants used a tablet or laptop with internet-access, to access a unique web address where our web-based tool was hosted. Research assistants were automatically informed by the web-based tool about the eligibility of the participant. Informed consent was obtained from all eligible participants using an automated computer-based form. Then, the tablet or laptop was handed to participants, who completed a self-administered online demographic and health survey, and then accessed the online shopping site to simulate a shopping situation. Participants completed the shopping task on the same day at the public place where they were recruited. After allocation, participants viewed a video explaining how to correctly interpret the assigned label. Each participant was asked to shop freely, to better mimic real-world grocery shopping conditions. Research assistants instructed participants as follows: take into account the assigned label and choose your preferred products. Participants were assigned an initial budget to do their shopping, although they did not pay actual money for their groceries. This budget corresponded to their weekly expenditure in groceries reported in the demographic survey, from 500-5000 Mexican pesos ($28-280 USD), in multiples of 500. No specific instructions were given related to the number or total cost of food products purchased. FOP nutrition labels were affixed on the food items of the virtual supermarket. The store displayed the name, price and the front of the pack image of 60 food products from 5 food groups (ready-made foods, dairy products, non-dairy beverages, salty snacks, and breakfast cereals). Products were shown on traditional shopping shelves. Participants could zoom in to look more closely at the products and their prices, and could click on the product to access a new pop-up window. This new window displayed product information (i.e., name and brand), a larger image of the front of the product packaging, and an area where they could select the amount or number of products they wanted to put in their shopping cart. The pop-up window was the only way in which participants could select the food products to purchase. Participants could also zoom in further on this pop-up to look more closely at the package and the nutritional label. After completing their shopping, participants revised their shopping cart and purchased their products. A brief feedback on the nutritional quality of the products in their shopping cart was provided as a retribution for their time.

Official Title
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Front of Pack Nutritional Labeling of Processed Foods Among Mexican Consumers

Conditions
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Food Labeling

Intervention / Treatment
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* Behavioral: Guideline Daily Amounts
* Behavioral: Multiple Traffic Light
* Behavioral: Warning Labels
* Behavioral: Video


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Consuming at least one of the five food groups included in the shopping site (salty snacks, beverages, dairy products, breakfast cereals and ready-made foods) Shopping for groceries at least twice per week Exclusion Criteria: Working in the food and beverage industry Having any of their direct family members working in the food and beverage industry

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Mexican Guideline Daily Allowance (GDA)<br>Guideline Daily Amounts (GDA) is a purely numerical and reductive labeling system, indicates the grams and percentages (according to the guideline-based daily intakes) per portion of kilocalories, saturated fats, other fats, sugars, and sodium, with no specific judgement, opinion or recommendation. | Behavioral: Guideline Daily Amounts<br>* All food items displayed the corresponding GDA label in the lower left corner of the front of the package.<br>Behavioral: Video<br>* Participants viewed a short (less than 1 min) video explaining how to interpret the label.<br>|
| Experimental: Ecuador's Multiple Traffic Light (MTL)<br>Multiple traffic light labels, an interpretive nutrient-specific FOP label, use the typical traffic light colors (green, yellow/amber, red) and text descriptors to indicate the high, medium, or low content of total fat, sugar and salt. | Behavioral: Multiple Traffic Light<br>* All food items displayed the corresponding MTL label in the lower left corner of the front of the package.<br>Behavioral: Video<br>* Participants viewed a short (less than 1 min) video explaining how to interpret the label.<br>|
| Experimental: Chilean Warning Labels in Red<br>Warning Labels (WL), another nutrient-specific interpretive FOP labelling scheme, include 'high in' symbols for products that exceed limits of energy, sodium, sugar and saturated fat. | Behavioral: Warning Labels<br>* Food products were labeled with High in labels In the lower left corner of the front of the package. In total, 37 of the 60 food products in the shopping site did not display a WL.<br>Behavioral: Video<br>* Participants viewed a short (less than 1 min) video explaining how to interpret the label.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean nutritional quality of the shopping cart | The Nutrient Profiling Scoring Criterion model was used as the main measure to evaluate the nutritional quality of the shopping cart. | On the date of randomization | 
| Mean nutritional quality of the shopping cart (negative nutrients) | The Nutrient Profiling Scoring Criterion baseline score, considering only negative nutrients, was used to explore a nutritional quality measure consistent with the key nutrients evaluated. | On the date of randomization | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean protein content | The mean protein content per 100g or 100 mL of the purchased items was calculated by dividing the total protein content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Mean fiber content | The mean fiber content per 100g or 100 mL of the purchased items was calculated by dividing the total fiber content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Mean sodium content | The mean sodium content per 100g or 100 mL of the purchased items was calculated by dividing the total sodium content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Mean sugar content | The mean sugar content per 100g or 100 mL of the purchased items was calculated by dividing the total sugar content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Mean saturated fat content | The mean saturated fat content per 100g or 100 mL of the purchased items was calculated by dividing the total saturated fat content in the shopping cart by the number of products purchased. | On the date of randomization, after completion of the online shopping simulation | 
| Mean energy content | The mean energy content per 100g or 100 mL of the purchased items was calculated by dividing the total energy content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Mean fat content | The mean fat content per 100g or 100 mL of the purchased items was calculated by dividing the total fat content in the shopping cart by the number of products purchased | On the date of randomization, after completion of the online shopping simulation | 
| Time to first product selection (minutes) | Calculated as the time required to buy a product after entering the online grocery store. | On the date of randomization, during the online shopping simulation | 
| Time spent looking at a product before deciding to buy it (seconds) | Estimated as the time between observing the food product on the pop-up window and clicking on the add to shopping cart button | On the date of randomization, during the online shopping simulation | 
| Time spent looking at a product before deciding not to buy it (seconds) | Estimated as the time between observing the food product on the pop-up window and going back to the shopping shelf | On the date of randomization, during the online shopping simulation | 
| Total time spent shopping (minutes) | Calculated as the time spent shopping, between entering and exiting the online grocery store. | On the date of randomization, after completion of the online shopping simulation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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food labeling, nutritional quality, label understanding, purchasing behavior