Consumer responses to various nutrition "front of pack" logos : a framed field experiment

In a laboratory experiment, we study consumer responses to 7 Nutrition ‘Front of Pack’ Logos. In addition to the Guideline Daily Amounts (GDA) logo, the six other logos vary according to three criteria: (i) Granularity (What object do we rate? Product vs. Nutrient), (ii) Reference Set (How do we distinguish between products? All Products vs. Product Family), and (iii) Policy Range (Do we include bad ratings? Green vs. Green and Red). 364 subjects, all parents accustomed to shopping, were asked to fill their shopping cart for their family for the next couple of days in an e-shopping environment. To do so, they could choose among 273 products grouped into 35 product families. They were then given the opportunity to revise their shopping cart after one of the seven logos had been exhaustively applied to all 273 products. The nutritional quality of a cart was assessed according to its salt, free sugar and saturated fatty acids content. We found that all of the seven logos significantly improved the nutritional quality of the shopping carts. On average, rating the product rather than the nutrient was more efficient. Informing on both healthy and unhealthy products was also more efficient on average but had significant toxic effects. The GDA logo lies at the median of our logo chart list. Unlike free sugar and saturated fatty acids, salt appears to be a particular case, as our logos proved to be insufficient for reducing its consumption.