In the general population, social disparities in Internet practices have been less described than disparities in health information access. Aim is to determine whether there are differences in the frequency of Internet use for health information among health seekers. We conducted an Internet-based survey from November 2006 to March 2007. We considered the 3720 residents of France who had searched for health information during the previous 12 months. This study reveals different uses of the Internet for health information seeking (HIS) between men and women and between the general population and people who work in the health sector. Health status, taking care of somebody who is sick, and active Internet use were associated with higher frequencies of online HIS to varying degrees. The effects of age and level of education were not clear or were not significant. Greater health concerns and some issues in the physician-patient relationship were associated with higher frequencies of Internet use for HIS in the general population. Considering that this increasing use of online tools for HIS is consistent with current public health policies that promote the development of the 'informed patient', one should remain cautious about these social disparities in online HIS practices.