An illustration photo of an elderly Internet user. Four out of five Internet users have searched for health information online, but the Web is still no substitute for the doctor when it comes to a personal medical issue, said a US study Thursday.

Four out of five Internet users have searched for health information online, but the Web is still no substitute for the doctor when it comes to a personal medical issue, said a US study Thursday.

The survey was based on telephone interviews with 3,001 adults in the United States in August and September 2010, conducted by Princeton Survey Research Associates International and published by the Pew Research Center's Internet and American Life Project.

Eighty percent of , or about 59 percent of the US population, searched online for one of 15 , whether a food recall, environmental hazard, or information on a specific disease, hospital or doctor.

One in three US adults said the Internet helped inform their own or those of someone they know, and only three percent said they or someone they know has been harmed by following online health advice.

Blogs were also popular for learning about other people's experiences.

Thirty-four percent of Internet users said they have read someone else's commentary or experience about health or medical issues on an online news group, website or blog.

But when asked about the last time they experienced a issue, 70 percent said they consulted a doctor or other health professional and the vast majority -- 65 percent -- said that interaction occurred offline.

Of the 54 percent who said they turned to a family or friend for support, 41 percent said the encounter happened away from the computer.

And although the use of social networking via sites like is on the rise, few people admitted to sharing intimate details about their health on them.

Eleven percent of social network site users, or five percent of adults, have posted comments, queries, or information about health or medical matters, it said.

Nine percent of social network site users, or four percent of adults, have started or joined a health related group on a social networking site.

"Social network sites are popular, but used only sparingly for health updates and queries," said the study.

Caregivers and people with chronic health woes were more likely than other social network users to use the medium for health causes.

Twenty-eight percent of caregivers and 20 percent of people with chronic conditions said they have gathered health information on such a site compared to 12 percent of other users.

Pew said the findings were similar to those reported in 2009.