The rise of the social web has brought a series of privacy concerns and threats. In particular, data leakage is a risk that affects the privacy of not only companies but individuals. Although there are tools that can prevent data losses, they require a prior step that involves the sensitive data to be properly identified. In this paper, we propose a new automatic approach that applies Named Entity Recognition (NER) to prevent data leaks. We conduct an empirical study with realworld data and show that this NER-based approach can enhance the prevention of data losses. In addition, we present and detail the implementation of a prototype built with these techniques and show how it can be used by both particulars and companies in order to handle data losses.