We demote old friends as new ones arrive: Research finds there is a natural limit to the number of people we can stay in touch with

  • British and Finnish researchers claim not enough brainpower for wide circle
  • Study tracked phone records of 24 students from school-university-work
  • Overall number of best friends remained roughly the same at five per person

Limited: British and Finnish researchers found we have limited brainpower to accommodate friendships

Limited: British and Finnish researchers found we have limited brainpower to accommodate friendships

It is often said that you can’t have too many friends.

But it seems that there is a natural limit the number of people we stay in touch with.

A study found that when we make new friends, by starting a new job or going to university, we downgrade or even drop old ones.

Even in today’s world when mobile phones, email and social networking sites such as Facebook make it easy to stay in contact with large numbers of people, we spend most of our time speaking to a small number of close friends and relatives. 

And while the friends may change, the number stays roughly the same.

The British and Finnish researchers believe we may only have the brainpower to invest emotionally and mentally in a limited number of people. 

Oxford University researcher Felix Reed-Tsochas said: ‘Although social communication is now easier than ever, it seems our capacity for maintaining emotionally close relationships is finite. 

‘At any point, individuals are able to keep up close relationships with only a small number of people, so that new friendships come at the expense of “relegating” existing friends.’

Dr Reed Tsochas asked 24 students in the final months of school to list all their friends and relatives and say how close to them they were.

The pupils filled in the questionnaire twice more after starting work or going to university.

They were also given free mobile phones and agreed to researchers could use their bills to work out who they called, when and for how long.

Putting the two pieces of information together showed, unsurprisingly, that most people have a small circle of close friends, who they spend most of their time talking to.

This inner circle is surrounded by group after group of ever more distant friends.

As the volunteers’ lives changed, this overall pattern, including the number of best friends, remained roughly the same, meaning that some close friends from childhood were dropped or downgraded as new friendships were struck up.

Dr Reed-Tsochas said: ‘Maybe my best friend is no longer the same person but the amount of time I allocate to my best friend is still the same.’

As we grow older we gravitate towards those we are around. The average number of best friends is five

As we grow older we gravitate towards those we are around. The average number of best friends is five

He added that this findings, published in the journal Proceedings of the National Academy of Sciences suggests that even with the advent of modern technology we are only capable of forming a limited number of true friendships. 

Chester University researcher Dr Sam Roberts said: ‘Our results are likely to reflect limitations in the ability of humans to maintain emotionally close relationships both because of limited time and because the emotional capital that individuals can allocate between family members and friends is finite.’  

Oxford University researcher Robin Dunbar, one of Britain’s leading evolutionary biologists, said: ‘It seems individuals’ patterns of communication are so prescribed that even the efficiencies provided by some forms of digital communication are insufficient to alter them.’

Professor Dunbar has previously estimated that the human brain is capable of juggling no more than 150 friendships but only five or so of these will be very close.  And two of these can expect to be ditched when we fall in love.