The fact that we see such high levels of loneliness, with substantial divergence across countries, explains why this is an important and active research area. Indeed, there are literally hundreds of papers that have used survey data to explore the link between loneliness, solitude, and health. Below is an overview of what these studies find.

The link between loneliness and physical health

Most papers studying the link between loneliness and health find that both objective solitude (e.g., living alone) and subjective loneliness (e.g., frequent self-reported feelings of loneliness) are correlated with higher morbidity (i.e. illness) and higher mortality (i.e. likelihood of death).

The relationship between health and loneliness can, of course, go both ways: lonely people may see their health deteriorate with time, but it may also be the case that people who suffer from poor health end up feeling more lonely later down the line.

Because of this two-way relationship, it’s important to go beyond cross-sectional correlations and focus on longitudinal studies – these are studies where researchers track the same individuals over time to see if loneliness predicts illness or mortality in the future after controlling for baseline behaviors and health status. Read more