Loneliness Affects Health
September 2007 - A study by University of Chicago psychologists, Louise Hawkley and John
Cacioppo published in Current Directions in Psychological Science investigated the relationship between social
isolation, loneliness, and physical deterioration associated with aging. Pointing out that loneliness is not the same
as solitude which can be highly valued they nevertheless conclude that social isolation and physical aging may have a
deleterious effect on health.
Researchers tested the hypothesis that the relatively mild impact of loneliness in the young may
have a cumulative effect by studying a group of college-age individuals and continuing an annual study of a group who
were between 50 and 68 years old when recruited.
Stressful experiences inevitably increase with age. Lonely participants in the older group reported
the same number of stressful life events but identified more sources of chronic stress and reported greater childhood
adversity. They also differed in how they perceived their life experiences, appearing more helpless and threatened and
less likely to seek help.
At the cellular level, researchers found that lonely participants had higher levels of epinephrine in
their urine. They explain that this is a "fight or flight" hormone suggesting a heightened state of arousal. As with
blood pressure, the physiological impact is likely to become more apparent with aging. Stress hormones are also
involved in fighting inflammation and infection, perhaps less effectively when loneliness is a factor.
Normal reliance on processes like sleep to recover from stress was also affected. Researchers
monitored the younger participants and found that the lonely had poorer quality sleep associated with numerous
"micro awakenings" and more daytime dysfunction. They point out that sleep tends to deteriorate with age, and
combined with loneliness this natural restorative process is probably further compromised.