New York, July 28 (IANS) People with close family and social ties have 50 percent more chances of living longer than those living isolated lives without friends, families or colleagues, says a new global study.

Isolation is as harmful as smoking 15 cigarettes a day, being alcoholic or obese, says the study led by Julianne Holt-Lunstad, an associate professor of psychology at Brigham Young University in Provo in Utah state.

The report, which is a compilation of 148 studies that followed 308,849 people – with an average age of 64 – for about seven and a half years, says that those with strong personal ties lived about four years longer than those with weaker social ties.

‘Our relationships come with more than just emotional benefits…relationships provide a sense of meaning and purpose in our lives – they can lead us to take better care of ourselves,” said Holt-Lunstad, lead author of the study published in the July issue of PLoS Medicine.

‘They (relationships) can influence our longevity and our health.”

Strong relationships had an effect comparable to that of quitting smoking and a greater effect than known risk factors such as obesity and alcohol abuse, she said.

‘Among adults over age 18, those with strong social relationships are likely to live an average of 3.7 years longer than those with weaker social relationships,” added study co-author Timothy Smith, who is a psychology professor at Brigham Young University.

With the quantity and quality of relationships decreasing in the age of technology, the authors said the challenge now is to put this information to good use.

The study covered North America, Europe, Asia and Australia.