Looking at the lives of the middle-aged and old people subjects, Hawkley and Cacioppo found that although the lonely ones reported the same number of stressful life events, the sources of chronic stress incidents were many more, and much more childhood adversity was recalled.
It was also observed that when faced with similar challenges, the lonelier people appeared more helpless and threatened. Unfortunately, they were less likely to seek help too, when stressed out.
Another observation was that when the psychologists took urine samples from both the lonely and the more contented volunteers, they found that the lonely ones had more of the hormone epinephrine flowing in their bodies.
Epinephrine can be termed as one of the body's "fight or flight" chemicals. High levels indicate that lonely people go through life in a heightened state of arousal. As with blood pressure, this physiological toll in all probability becomes more apparent with aging.
As the body's stress hormones are deeply involved in fighting inflammation and infection, it is apparent that loneliness contributes to the wear and tear of aging through this pathway as well.
When people experience stress, the bodies normally rely on restorative processes like sleep to shore up. But when the researchers monitored the younger volunteers' sleep, they found that the nights of the 'lonely', were broken by many "micro awakenings."