Researchers have uncovered another difference between the sexes: women get more, deeper wrinkles around their mouths than men do as they age.

And they have identified several reasons for the gender imbalance.

The research, which appears in the latest issue of the Aesthetic Surgery Journal, looked at both male and female cadavers, studying the skin around the upper lip.

They found several key differences between the sexes.

One of the major ones that lines are deeper in women is that women have fewer sweat glands around the mouth than men.

Another factor that may make women more prone to wrinkling included is that they have fewer blood vessels meaning reduced blood flow to that region of their face.

Also, their muscles around the mouth are closer to the skin than in men, pulling the skin in tighter and potentially causing wrinkles.

Another factor is hormones- the hormone oestrogen is thought to play a role in gender differences in health and disease