Impact of changes in relationship status on smoking behavior and body weight

This paper examines whether and how changes in relationship status (i.e., cohabitation, marriage, separation, or divorce) affect individuals' smoking behavior and body weight. Using German Socio-Economic Panel data, this study accounts for differences between treated (i.e., those affected by a specific family event) and untreated participants since treatment and control groups differ with respect to several characteristics such as age, which may bias the results. Therefore, regression-adjusted matching is employed for each family event separately. This study, thus, takes steps towards disentangling causality from correlation. Overall, changes in family composition (such as moving together with or separating from the partner) impact the probability to start or quit smoking and lead to changes in body weight. In particular, smoking behavior and body weight are predominantly affected by forming or dissolving a household, rather than by marriage or divorce: cohabitation leads to weight gain; separation from a partner leads to weight loss, increased smoking initiation, and decreased smoking cessation.