A little over 50 years ago, the endocrinologist Hans Selye (1956) published The Stress of Life, summarizing his research on the physiological consequences of stress.1 Because he was working with laboratory animals, Selye conceptualized stress (or stressors) as exposures to noxious envi- ronmental stimuli, such as extreme temperatures, electric shocks, or food deprivation. He identified three stages of physiological reactions to noxious events: the alarm, resistance, and exhaustion stages. Further, he linked the exhaustion stage, i.e., the depletion of bodily defenses against stress, to subsequent risks of high blood pressure, heart dis- ease, and other diseases of adaptation. This cas- cade of physiological reactions to stressors and their harmful consequences for physical health were later confirmed in human subjects. But popu- lation studies of the impacts of stressful experi- ences did not take off until psychiatrists Thomas Holmes and Richard Rahe (1967) created the
Social Readjustment Rating Scale to measure stressors that were social in nature. When they reviewed Navy medical records, Holmes and Rahe found that major changes in patients’ lives often preceded their doctor visits and hospitalizations. They hypothesized that major life events required individuals to make extensive behavioral readjustments in their daily lives and that too many changes in a short period of time could overtax individuals’ abilities to cope or adapt, leaving them more vulnerable to infec- tion, injury, or disease. Holmes and Rahe extracted