Poor relationships damage our health.  Recent research powerfully demonstrates this point (Stinson, Logel et al. 2008).  In these studies, relationships were assessed in three different ways - relationship quality (closeness, trust, satisfaction), number of friends, and relationship stress.  Sheldon Cohen (Cohen 2004) has argued that these three aspects of relationships are all important in the relationships-health link - emotional closeness, broader social network, and low interpersonal conflict.  In this Stinson et al research, all three aspects were assessed and all three predicted subsequent health.  In the team's second study, they showed relationship stress (function) and number of friends (structure) were independently linked to health outcomes - the former a bit more strongly than the latter.  More stress and fewer friends both predicted more health difficulties.  Health difficulties too were assessed in three different ways - simply by asking participants whether they had developed any health problems during the study period, by asking about time off work, and by asking about visits to doctors.  Poor relationships led to increases in all three of these health indicators.