I recently watched a BBC2 biography on the great opera singer, Maria Callas. Respectful it was not, for instance it told how she had given birth to a son by Aristotle Onassis and explained that in her early years she was – oh, how can one put this delicately? – somewhat pudgy. According to the biography, she then ingested the eggs of tapeworms in order to lose weight. Now, I have known people who have embarked on the Dr Atkins diet and tried the cabbage soup plan, but ingesting the eggs of tapeworms strikes me as a tad extreme.