“Extreme examples show infants in custodial care who lack human contact fail to thrive and often die, and indeed, social isolation or solitary confinement has been used as a form of punishment,” said Holt-Lunstad. “Yet an increasing portion of the American population now experiences isolation regularly,” she said.
Loneliness and social isolation have both been associated with poor health. One study reported by Medical News Today last year, for example, suggested that loneliness may be linked to Alzheimer’s disease, while other research linked social isolation to reduced survival for breast cancer patients.
To illustrate the influence of social isolation and loneliness on the risk for premature mortality, Holt-Lunstad presented data from two research reviews.
The first involved 148 studies, representing more than 300,000 participants, and found that greater social connection is associated with a 50% reduced risk of early death.The second study, involving 70 studies representing more than 3.4 million individuals from North America, Europe, Asia and Australia, examined the role that social isolation, loneliness or living alone might have on mortality. Researchers found that all three had a significant and equal effect on the risk of premature death, one that was equal to or exceeded the effect of other well-accepted risk factors such as obesity .
“There is robust evidence that social isolation and loneliness significantly increase risk for premature mortality, and the magnitude of the risk exceeds that of many leading health indicators,” said Holt-Lunstad.