Don’t search for information on medical issues or drugs

While Google says that it prohibits advertisers “from remarketing based on sensitive information, such as health information or religious beliefs,” the company’s privacy policy reserves the right to record your search results, associate them with your IP address or Google account, and then use that information to target ads on Google properties and across the web. Neal Ungerleider recently reported that researchers have found looking up medical and drug information online is a major privacy risk.

Tim Libert, a doctoral student at the University of Pennsylvania’s Annenberg School for Communication found that more than 90% of the 80,000 health-related pages he looked at exposed user information to third parties. The pages he researched included commercial, nonprofit, educational, and government websites, and the finding is particularly unsettling given a Pew Research Center finding that 72% of Internet users in the United States look up health-related information online. Even worse? Google collects information from 78% of the pages that Libert looked at, which gives advertisers an easy way to figure out that a user has specific health issues, and find out what issues those are. Visits to pages on HIV/AIDS, for instance, can be combined with a user’s browsing history and lead to ads for HIV and AIDS treatments, which Ungerleider notes effectively outs their HIV status.