The article deals with the explanation communicative strategy in the American popular medical discourse based on the Internet sources. The thematic, adaptive and axiological features of explanation in this strategy are found out. The themes of information cover the issues of structure and functioning of a human body, maintenance of comfortable life conditions, efficient ways to prevent and cure widespread diseases. The adaptation of information is shown in the communicative tactics of fact describing, features of notions, oppositions of signs of these notions, exemplification, constructing simple explanatory schemes. The value priorities are revealed by explanation of purposefulness of behavioral standards which are based on common sense, strong will, self-control and optimism.