What you find disgusting is not a unique aspect of your multi-faceted personality but falls neatly into one of five categories common to all of us, psychologists have discovered.
Karen Barker of City University and Graham Davey of Sussex discovered that disgusting things are: foods of animal origin such as offal; the human body and its products such as greasy hair; invertebrate animals such as maggots (women only); gastro-enteric products such as vomit; and sexual activities such as incest.
They conclude that most disgust has the function of preventing illness, disease and infection, except for sexual disgust, which may be cultural.