Previously, a number of studies have suggested that psychological well-being confers a wide range of health benefits, including to reduce cognitive decline.  Carolyn Crandall, from the University of California/Los Angeles (UCLA; California, USA), and colleagues  analyzed data from the two waves of the Study of Midlife in the United States, which included a national sample of adults who were interviewed in 1995 and again 10 years later about various domains of psychological health. At the time of the second interview, 716 of the participants underwent imaging scans of the lumbar spine and femoral neck.  The team found that measures of psychological status positively associated with bone mineral density (BMD).   For each BMD standard deviation, the association of average long-term positive affect with femoral neck BMD was 0.06; similarly, the association of having positive relationships with others had an association with femoral neck BMD of 0.068.  Self-acceptance also had a positive association of 0.063.  The researchers discovered that the strongest association was for having a purpose in life, where the association for femoral neck BMD was 0.114 and the association at the lumbar spine was 0.080.  These positive associations remained even after adjustment for confounding factors.