Testing Ultraprocessed Food Labels in Chile

Evaluating the Effectiveness of an Ultraprocessed Food Warning Label in Chile

The goal of this experiment is to examine the effects of a warning label signaling that a product is ultraprocessed among a sample of Chilean parents. The main questions this experiment aims to answer are:

Do ultraprocessed warning labels on their own impact product purchase intentions?

Do ultraprocessed warning labels impact product purchase intentions in the presence of nutrient warning labels?

Do ultraprocessed warning labels help more consumers identify ultraprocessed foods?

Participants will be randomly assigned to a control arm or an ultraprocessed warning label arm. In both arms, products will carry nutrient warning labels, which are Chile's current policy. Participants will see three similar products, all of which will be ultraprocessed: one not high in any nutrients of concern, one high in sodium, and one high in sodium and saturated fat. For each product, participants will rate their purchase intentions and indicate whether they believe the product to be ultraprocessed. Researchers will compare results across arms.

Study Overview

• Status: Completed
• Conditions: Diet, Healthy
• Intervention / Treatment: Behavioral: Control; Behavioral: Ultraprocessed warning label

Detailed Description

Participants will complete an online randomized experiment programmed in Qualtrics. After providing informed consent, participants will be randomly assigned to one of two arms: control (i.e., no ultraprocessed warning label) arm or ultraprocessed warning label arm. In both arms, products will carry nutrient warning labels, which are Chile's current policy.

In random order, participants will see three similar mock bags of potato chips. All products seen will be ultraprocessed, and thus carry an ultraprocessed warning label in the ultraprocessed warning label arm. Additionally, one of the products will not be high in any nutrients of concern, one product will be high in sodium, and one product will be high in sodium and saturated fat. For each product, participants will rate their purchase intentions, perceived healthfulness, and indicate whether they believe the product to be ultraprocessed.

• Study Type: Interventional
• Enrollment (Actual): 3645
• Phase: Not Applicable

Contacts and Locations

Study Locations

• United States
  • North Carolina
    • Chapel Hill, North Carolina, United States, 27599
      • The University of North Carolina at Chapel Hill's Gillings School of Global Public Health

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• 18 years or older
• Parent or guardian of child between 2-14 years old who has never been diagnosed with diabetes, high blood sugar, pre-diabetes or insulin resistance
• Residing in Chile

Exclusion Criteria:

• Less than 18 years old
• Not parent or guardian of child between 2-14 years old who has never been diagnosed with diabetes, high blood sugar, pre-diabetes or insulin resistance
• Not residing in Chile

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Active Comparator: Control	Behavioral: Control; Products do not carry ultraprocessed warning label. To match the current Chilean legislation, products carry octagonal nutrient labels when applicable.
Experimental: Ultraprocessed warning label	Behavioral: Ultraprocessed warning label; Products carry ultraprocessed warning label. To match the current Chilean legislation, products carry octagonal nutrient labels when applicable.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Purchase intentions, mean score	How likely the participant would be to buy products will be measured by survey. Response options will be on a 5-point scale from "very unlikely" (coded as 1) to "very likely" (coded as 5), with higher scores representing a higher likelihood of buying products.	During exposure to intervention (i.e., study stimuli), assessed during one-time online 10-minute survey.
Correct identification of products as ultraprocessed	Correct identification of products as ultraprocessed will be measured by survey. Response will be coded in a dichotomous 0-1 range, where 1 indicates that the participant correctly identified the products as ultraprocessed and 0 indicates that the participant did not correctly identify the products as ultraprocessed.	During exposure to intervention (i.e., study stimuli), assessed during one-time online 10-minute survey.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Perceived product healthfulness, mean score	How good or bad it would be to consume the product every day will be measured by survey. Response options will be on a 5-point scale from "very bad" (coded as 1) to "very good" (coded as 5), with higher scores representing a higher perceived product healthfulness.	During exposure to intervention (i.e., study stimuli), assessed during one-time online 10-minute survey.

Collaborators and Investigators

• Sponsor: University of North Carolina, Chapel Hill
• Collaborators: Instituto de Nutrición y Tecnología de los Alimentos; Bloomberg Philanthropies
• Investigators: Principal Investigator: Aline D'Angelo Campos, MPP, University of North Carolina, Chapel Hill

Study record dates

Study Major Dates

• Study Start (Actual): July 14, 2025
• Primary Completion (Actual): August 31, 2025
• Study Completion (Actual): August 31, 2025

Study Registration Dates

• First Submitted: February 18, 2025
• First Submitted That Met QC Criteria: February 18, 2025
• First Posted (Actual): February 24, 2025

Study Record Updates

• Last Update Posted (Estimated): September 9, 2025
• Last Update Submitted That Met QC Criteria: September 5, 2025
• Last Verified: April 1, 2025

More Information

Terms related to this study

• Other Study ID Numbers: 24-2896b

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: YES
• IPD Plan Description: The Study Protocol and Statistical Analysis Plan will be shared prior to data collection. After data collection and analysis, a de-identified version of individual participant data and the analytic code will be shared through the Open Science Framework (OSF).
• IPD Sharing Time Frame: The Study Protocol and statistical analysis plan will be available by March 2025 (prior to data collection). A de-identified version of the data collected and analytic code used will become available after data collection and analysis and will remain available indefinitely.
• IPD Sharing Access Criteria: Open access.
• IPD Sharing Supporting Information Type: STUDY_PROTOCOL; SAP

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No