Health does not inevitably and irrevocably decline with age. Many people advance to old age in good health, while others experience substantial disability and morbidity in early middle age or younger (House et al. 1994). Furthermore, individuals can recover from health problems and experience improved health at any age (Taylor et al. 2002). Health behaviors over the life course explain a great deal of the health heterogeneity and change that we see at any given age (Kaplan 1991). A life course framework, therefore, can suggest why, when, and how particular social ties affect health behaviors similarly and differently across and within stages of life. Moreover, given the emphasis of the life course perspective on how individual lives are embedded in larger contexts, such a framework is useful for thinking about how the link between social ties and health behavior contributes to demographic disparities in health, although that particular topic is beyond the scope of this review.
