LONDON - Men can guess a woman’s age even when they are dead drunk, according to a new study.

Males accused of unlawful sex with a minor can claim on ‘reasonable grounds’ that they were unaware of the girl being underage.

Other factors that may influence his perception would also be taken into account, such as how much alcohol he had drunk or how much make-up the girl was wearing.

This study sought to ascertain if these factors (alcohol and make-up) would alter people’s perceptions about women’s ages. Two hundred and forty people were asked to look at photos of women and then comment on their age and attractiveness.

All the participants were heterosexual, aged between 18 and 70 with an equal split between men and women. Half of the participants had consumed alcohol before the task.

The participants looked at photographs of 10 young women, aged 17. Some of the photographs were digitally altered to give the faces a younger or older appearance and in both some make-up was applied digitally.

The results showed that drinking alcohol and the use of make-up had a minimal effect on the men’s perception of the ages of the photographed women, a release of the British Journal of Psychology said.

Vincent Egan who led the study said: ‘This study suggests that alcohol consumption and make-up use do not interfere with how old we perceive someone to be.’

Another interesting finding was that overall participants who drank alcohol actually rated all the women in the photos as less attractive (compared to the participants who hadn’t drunk alcohol). This is contrary to the commonly held notion of ‘beer goggles’.

These findings were published Monday in the British Journal of Psychology.