"Belonging to social groups and networks appears to be an important predictor of health - just as important as diet and exercise. This point is demonstrated by a study of 655 stroke patients reported in 2005 by Bernadette Boden-lbala, professor of sociomedical sciences and neurology at Columbia University, and her colleagues. Patients who were socially isolated were nearly twice as likely to have another
stroke within five years as were those with meaningful social relationships. In fact, being cut off from others appeared to put people at far greater risk of another stroke than traditional factors such as having coronary artery disease or being physically inactive (each of which increased the likelihood of a second stroke by about 30 percent).

"Such effects are not restricted to those who have a significant health problem. In a 2008 study epidemiologists and health researchers Karen Ertel, Maria Glymour and Lisa Berkman of the Harvard School of Public Health tracked 16,638 elderly Americans over a period of six years. The findings, published in the American Journal of Public Health, revealed significantly less memory loss in those who were more socially integrated and active.

"Using an even more prosaic health indicator, a 2003 study by Carnegie Mellon University psychologist Sheldon Cohen and his colleagues showed that a diverse social network made people less susceptible to the common cold. Their work, published in Psychological Science, indicated that the least sociable people in their sample were twice as likely to get colds as those who were the most sociable - even though the more sociable people were probably exposed to many more germs. ...

"A body of recent research shows that belonging to multiple social groups is particularly critical in shielding people from the health hazards of important life changes. Consider the marathon runner whose injury prevents her from ever running again. Anyone might be devastated by such an injury, but the consequences are greater for a person who
defines herself exclusively in terms of being a runner. Likewise, think of the workaholic who never has time for his family or friends and therefore finds adjustment to retirement particularly difficult.

We hypothesize that it is best not to have all of your eggs (social identities) in one basket in case misfortune strikes. It is better, research suggests, to spread your metaphorical eggs around a number of baskets (that is, to have multiple social identities) so that the loss of one still leaves you with others.

"Three of us (Haslam, Haslam and Jetten) recently examined this notion in a study we conducted with other clinical and social psychologists - Abigail Holmes, W. Huw Williams and Aarti Iyer - at the University of Exeter in England. In the study, published in 2008 in Neuropsychological Rehabilitation, we examined the changing circumstances of 53 people who had recently suffered a stroke. Life satisfaction after the stroke was much higher for those who had belonged to more social groups before their stroke. Further analysis suggested the reason for this finding was that stroke patients who had previously belonged to a lot of groups had a bigger social support network to fall back on."

Jolanda Jetten, Catherine Haslam, S. Alexander Haslam and Nyla R. Branscombe, "The Social Cure," Scientific American, Mind Issue,