Man smiling as woman touches his faceOkay, so it might not be the most surprising news you've heard, but recent research has revealed that the guys simply can't help being pleased to see you.

Scientists have now confirmed that the presence of a gorgeous gal can produce a testosterone boost for the boys.

With the added bonus of a release of cortisol, the chaps will notice a feeling of alertness and wellbeing whilst chatting to an attractive member of the opposite sex.

Psychologists at the University of California discovered that just a five minute chat with an attractive woman raised testosterone levels by 14 per cent and anti-stress hormone cortisol by a whopping 48 per cent.

The same effect in animals is known as the "mating response". Testosterone is linked to the male libido and a general all-round energy boost, while cortisol boosts alertness and calms the nerves.

Put the two together and the boys will be feeling on top of the world.

And Dr Leslie Knapp, a biological anthropologist at the University of Cambridge, confirmed what the girls were already guessing.

She told The Telegraph: "It all boils down to sex. High levels of testosterone are associated with boosting sexual performance whereas cortisol helps focus your energy and helps you deal with anxiety."

Of course, we imagine those suffering a knockback experience a sharp decline in their feelings of wellbeing.