APA Dictionary of Psychology

actions one takes to achieve or maintain physical and mental health and to prevent or reduce illness. These actions are often responses to one’s conscious or nonconscious attitudes about health, illness, and the requirements for attaining and maintaining wellness. They are also influenced by social factors, such as the health norms of one’s social group, and by structural factors, such as access to health care services. A health behavior may consist of a single or occasional act (e.g., getting a tetanus shot every 10 years, using sunscreen at the beach) or a regularly repeated event (e.g., going to the gym three times a week, adhering to daily medication regimens for a chronic illness). More broadly, however, the term also encompasses behaviors that are detrimental to well-being, such as cigarette smoking, excessive alcohol consumption, and poor diet.

Of the many theories about health behavior that have proliferated over the years, the health–belief model, the theory of planned behavior (and its earlier incarnation, the theory of reasoned action), social-cognitive theory, and the transtheoretical model are particularly influential. They differ in what they consider to be the significant determinants of behavior and the pathways to behavior change, but they share the assumption that health behavior arises primarily from intrapersonal factors and processes (e.g., beliefs, attitudes, motivations, cognitions), and they conceptualize extraindividual influences (e.g., cultural norms, access to resources, social–environmental barriers) as being mediated or filtered through the individual.