Food Swaps to Improve the Healthfulness and Reduce the Carbon Footprint of Grocery Purchases

"Participants will view health grade labels on all products in the online grocery store indicating their healthfulness as estimated by United Kingdom Ofcom Nutrient Profiling Model scores. The health score labels will mimic Nutri-Score labels, a labeling system used in some European countries, showing a color-coded grade of A (green) through F (red) on each product. Products with A and B labels will meet the United Kingdom's cutoff for products that can be marketed to children and C, D and F labels products are less healthy than this cutoff (based on tertiles of Ofcom scores within each food group). When participants attempt to add a less healthy product to their cart (e.g., C, D or F health label), the store will automatically suggest a healthier product from the same category (e.g., with a A or B health label)."

"Participants will view climate grade labels on all products indicating their climate impact. The climate impact is calculated as the greenhouse gas emissions associated with producing the product in carbon dioxide equivalents (CO2-eq) per 100g (i.e., carbon footprint). Labels will be applied based on quintiles of carbon footprints in each food group. When participants attempt to add a high-climate-impact product to their cart (e.g., with a C, D, or F climate label), the store will automatically offer them swaps to more climate-friendly products (e.g., with a A or B climate label)."

"Participants will view both the health and climate grade labels on all products in the online grocery store. When participants attempt to select a product with a C, D, or F label on either dimension to their cart, the store will automatically offer them swaps to products that offer improvement over the original food on at least 1 dimension (health or climate-friendliness) and were at least as good or better on the other dimension, with the additional guardrail that the store never suggests products with a C, D or F label on either dimension."

Participants will not view any extra labels or be offered any swaps in the online grocery store.