Do you have one clearly defined best friend, or a couple of really good friends? Lots of TV shows and books see the female character with one very best friend (Meredith and Christina on Grey’s Anatomy, Jess and Cece on New Girl, Monica and Rachel in Friends), but is this true to real life?

Alice Robb from Newstatesman did some research into what being “best friends” actually means when you’re an adult. One woman she talked to said that her “best friend” was changed depending on the other person’s geographic location, relationship statues and job: “I have a high-school bestie, a college bestie, a bestie from my DC days, etc. that all make up my ‘bestie tier’.

“I think of it as concentric circles – a small number of people are my core support/friend group, the centre of my social/emotional world, and I call them all ‘my best friend’ or besties.”

The BFF trend seems to be solely a female one, Oxford evolutionary psychologist Robin Dunbar said that: “The BFF (or “[same sex] Best Friend Forever”) seems to be a peculiarly female thing.

“Men, once they couple off, prefer their best friend to be their romantic partner.”

Psychologists say that relying on one person for all your emotional needs is unhealthy. They say that labelling one friend as your best friend puts the same pressure onto your friendship as say, a romantic relationship would hold, only with less benefits. Dunbar said: “Because these relationships are very intense (in a non-sexual way), they are also very fragile. When they bust, they bust forever and acrimoniously.”

What do you think – are BFFs ok, or should we stop choosing favourites from our group of average friends?