The eco-labels in food products is an increasing presence to underline a particular attention to sustainability issues by producers and, recently, also by retailers, through their private labels (PLs). In the last years there has been a proliferation of eco-labels, generating sometimes a real confusion in consumers' mind. Nevertheless, some of them could be really considered as a decisive factor to influence the purchasing process. It could be possible to affirm that they acquired a real "power", producing a tangible effect on consumers' behaviour. The present work is an attempt to calculate the effectiveness of one of the most well-known eco-label, "Euro-leaf", that indicates products coming from organic farming. The aim of the analysis is to evaluate its incidence in the choices related to food proposals. In particular, the latter have been considered in a double way, exploring the different categories among branded and PL offers, in the continuous challenge between these two branding policies in the retail sector. Therefore, to carry out the research, the methodology adopted has been the diffusion of a questionnaire to a wide sample. More of 1.000 Italian consumers have been reached using an on line platform, shaping a stratified sample. The data elaboration shows a final result where the euro-leaf logo is able to have the same positive influence on buying propensity related both to branded and PL products. Observing the dimension of this influence, valid information are provided for practitioners and researchers to highlight a market trend where all the potentials have not yet been expressed.