Socialising with friends was found to be beneficial
Good friends promise to be there for you, and their presence can actually help you live longer, researchers say.
Australian scientists said having friends around in old age can do more for life expectancy than having family members around.
The team looked at how a range of social, health and lifestyle factors affected the survival rates of more than 1,500 people over 70.
The research is in the Journal of Epidemiology and Community Health.
The team took data from the Australian Longitudinal Study of Aging (ALSA), which began in 1992 in Adelaide, South Australia.
As part of the study, people were asked how much personal and phone contact they had with their various social networks, including children, relatives, friends and confidants.
The team then looked at each participant's survival rates over the following decade, checking them after four years, and then at around three yearly intervals.
It was found that close contact with children and relatives had little impact on survival rates over the 10 years.
However, those with the strongest network of friends and acquaintances were statistically more likely to be alive at the end of the study than those with the fewest.
After controlling for demographic, health and lifestyle variables, the people in the top third of friends social networks were found to be 22% less likely to die over the following decade than people in the lowest third.
This was evident even if the person had been through major changes such as the death of a spouse or close family members, and the relocation of friends to other parts of the country.
The researchers, led by Lynne Giles at Flinders University, in Adelaide, said the benefits may be due to the fact people could choose their friends, as opposed to family members.
Writing in the Journal of Epidemiology and Community Health, they said: "Discretionary relationships, with friends and confidants, as compared with relationships where there is less choice concerning interactions, with children and other relatives, have important positive effects on survival."
They also suggest that friends may encourage people to look after their health, and help reduce feelings of depression and anxiety at difficult times.
In an editorial in the same journal, Anthony Jorm, of the Australian National University, said: "We are now arguably at a point where a large-scale trial is warranted.
"Befriending schemes have been developed and trialled for people with depression and could provide a model for a potential intervention.
"If such a trial successfully showed that social networks could be modified with benefits to health, this would provide the basis for more widespread health promotion, with the aim of increasing friendship networks in the whole population."
Dr Lorna Layward, research manager for Help the Aged, said: "As we get older we may lose friends, so it's essential to constantly build and maintain new relationships.
"Interestingly, we know that the quality of social life for many women actually improves with age, so it goes to show that we really do benefit from chatting and feeling valued among friends."
She added: "Importantly, as a society, we do need to include older people more and encourage communities to build the kind of environments that allow social networks to blossom.
"We know that for many older people, transport can be a barrier to getting out and about to visit friends, so offering a lift to an older neighbour would mean more than most would realise."