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.

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.

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

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).

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.

Open access.