The primary aim of this study is to evaluate the relationship between overall levels of stress and telomere length. It is hypothesized that the high stress group (based on the Perceived Stress Scale)compared to low stress group will have shorter telomere length. A secondary aim is to evaluate whether different types of stress have differing degrees of association with telomere length. An exploratory aim is to assess for gender differences in the association between stress and telomere length. The investigators are collecting a number of other measures, including demographics, work sector, perceived social support, and medical history, in order to adjust for potential confounders in the analysis.