Eighty percent of Internet users said they used the Internet to research health information in 2004--virtually unchanged from 2002, when 79 percent of online users said they researched health issues online, according to a report released this week by the Pew Internet & American Life Project. But the study, "Health Information Online," found several key differences between 2002 and 2004 when it came to researching health information online. Last year, 51 percent of online consumers used the Web to research diet or nutrition, compared to 44 percent in 2002--while 42 percent of consumers in 2004 sought out information on exercise, versus 36 percent three years ago. Also, 31 percent of online consumers used the Web to investigate health care, compared to 25 percent in 2002. The report was based on a telephone survey of 914 adults, conducted last November.