Introduction
Interest in behaviors that have important impacts on our health and well being is based upon
two assumptions; (a) that a significant proportion of the mortality from the leading causes of
death is caused by the behavior of individuals, and (b) that such behavior is modifiable
(Conner and Norman 1996). Behavior is held to exert its influence on health in three basic
ways: by producing direct biological changes, by conveying health risks or protecting against
them, or by leading to the early detection or treatment of disease (Baum and Posluszny 1999).
This chapter begins by offering a definition of health behavior and the different types of
health behavior. The prevalence of key health behaviors and their relationship to morbidity
and mortality is then examined. The chapter then considers who performs these different
behaviors, why they might do so, and how health enhancing behaviors might be encouraged
and health impairing behaviors discouraged.