The Many Faces of Stress: Three Factors that Predict Physical Illness in Young Adults

Three studies examined how various forms of stress uniquely contribute to physical illness. We compared negative affect and perceived stress in Study 1, neuroticism and perceived stress in Study 2, and negative affect, neuroticism, and perceived stress in Study 3. We also controlled for health-related covariates (i.e., exercise, nutrition, substance use, and BMI). In all three studies (ns = 271, 577, and 300), participants completed online surveys for course credit. The results of Study 1 demonstrated that both negative affect and perceived stress predicted physical illness. In Study 2, neuroticism and perceived stress each predicted illness symptoms, and an additional interaction between neuroticism and perceived stress, were found. In Study 3, where all three stress factors were included, only negative affect predicted illness symptoms. Taken together, these results suggest that negative affect uniquely explains most of the variance in physical illness symptoms while controlling for other forms of stress.