By using the theories of help-seeking behavior and health-information seeking, this article demonstrates the relationship between chronic illness, retrieving health information from the Internet and changing health behavior. Research on the impact of health information on the Internet and changing health behavior is fairly new, given the growth of the Internet in recent years. Using US data on Internet use within the US population, multiple regression analysis was performed to explore the relationships between chronic medical conditions and frequency of Internet use, as well as changes in health behavior due to frequency of Internet use. The findings suggest that it is not merely the presence of a particular chronic illness, but rather the total number of chronic conditions that determine Internet use. Also, the more frequently a person uses the Internet as a source of health information, the more likely they are to change their health behavior.