The strategic development of novel nanotechnologies will be determined by their public acceptance, which in turn may be influenced by public perceptions of the risks and benefits associated with the specific applications. At the present time, public opinions towards nanotechnologies remain largely inchoate, although this is likely to change with increasing public exposure to relevant information. In two experiments, a total of 618 participants, from the UK population, were provided with different risk–benefit information on nanotechnology application in food. The results show that the provision of both risk and benefit information does not influence average attitude, but results in some individuals becoming more positive and less ambivalent and others more negative and less ambivalent towards nanotechnologies. A third group maintained a neutral attitude and became more ambivalent. It is concluded that to understand public opinion formation about nanotechnology keeping track of polarization and ambivalence is important.