Men and women meet their best friend for life in their late teens – but shed most of their chums at different stages.
Men start losing friends from their support group from their mid-20s, with the circle of people they rely on dramatically reducing.
But women hang on to their closest confidantes well into their late 40s and only start to lose them when grandchildren come along.
Around 75 per cent of women have a best friend, researchers found, someone they have known, on average, since the age of 18.
Men's best male friends are people they met at the age of 19.
