Front-of-pack nutrition labels (FOPNLs) have been developed since 1989 to curb the increasing prevalence of obesity and non-communicable diseases (NCDs) and to promote healthy consumption choices. While several countries have introduced their own labeling schemes on a voluntary basis, the European Commission aims to harmonize a FOPNL system that will be mandatory for all member states. This paper summarizes a contribution to the current debate on FOPNLs from Italian and Spanish researchers working in the fields of human nutrition, nutritional epidemiology and public health education and communication policy before the final decision on FOPNLs to become mandatory in Europe is taken.