Sociologists rarely study personality, but psychological research stresses the role of personality in shaping health habits. First, some personality characteristics are associated with health behavior. For example, individuals who are low on conscientiousness (“prudent, planful, persistent, dependable,” Friedman 2000, p. 1099) or high on hostility engage in more risky health behavior (Smith & Gallo 2001, Williams 2001). Second, personality may be associated with health behavior in several ways related to social ties. Personality may directly influence the formation, duration, and quality of social ties that, in turn, influence behavior. For example, low neuroticism and high extraversion are positively associated with quantity and quality of social ties (Smith & Gallo 2001), and conscientious individuals have more stable relationships over time (Friedman et al. 1995). Third, social ties may have a stronger effect on health behavior for those with certain personality characteristics. For example, more conscientious people may do more to protect their own health so that they can care for others. This last example suggests another interrelationship between mechanisms. That is, social control could operate more strongly for those who are
