The rebellious 21-member coalition includes Cadbury Schweppes, Coca-Cola, Nestle, Danone, Masterfoods, PepsiCo, and Unilever, as well as major retailers.
Their plan is to label food and beverages with a numerical guideline daily amount (GDA). The Food Standards Agency, the official food watchdog, wants to use the "traffic light" system.
The coalition is afraid that shoppers would be discouraged from buying products with red labels on them. Critics say the GDA system is flawed because nearly half of adults lack the numerical skills to understand what the labels mean.
Called "Know what's going inside you," the TV, online and print campaign aims to explain how to use the GDA labels, which tell consumers the percentage of the adult male GDA of four key nutrients in each product.
The ads will run from January to August.