Washington:
The quality of social life has a greater impact than diet and exercise on a person's health and well-being, a new study says.
An international team has carried out the study and found that the quality of a person's social life significantly reduces the risk of conditions like stroke, dementia and even the common cold.
Lead researcher Prof Alex Haslam of the University of Exeter said: "We are social animals who live and have evolved to live in social groups. Membership of groups, from football teams to book clubs and voluntary societies, gives us a sense of social identity.
"This is an indispensable part of who we are and what we need to be in order to lead rich and fulfilling lives. For this reason groups are central to mental functioning, health and well-being."
The researchers have based their findings on an analysis of a number of recent studies.
A 2008 study of stroke sufferers showed that being able to maintain valued group memberships played an important role in positive recovery as an ability to overcome cognitive difficulties. After their stroke, people's life satisfaction increased by 12 per cent for every group membership.
Likewise, a 2009 study of residents entering a new care home showed that those who participated as a group in decisions related to the decoration of communal areas used those areas 57 per cent more over the next month and were far happier as a result. In contrast, the use of space by residents in a control group declined by 60 per cent.
Co-researcher Jolanda Jetten from the University of Queensland said: "New research shows just how important groups and social identity are to well-being. This is something that people often overlook in the rush to find medical solutions to problems associated with ageing, but it is time that these factors were taken much more seriously."
The findings are published in the latest edition of the 'Scientific American Mind' journal.