After observing 500 drinkers in bars, Dr. Glenn Wilson, a consultant psychologist at King's College, London, categorised all revellers into one of eight different personality types, which could be found out by their drinking style.
He analysed the drinkers' body language, and then advised on their openness to being approached.
''The simple act of holding a drink displays a lot more about us than we realise - or might want to divulge,'' the Telegraph quoted Wilson as saying.
''The next time you're in a bar, it might be worth thinking about what you're saying to the people around you just by the way you're holding your glass,'' he added.
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