Denmark is the first country in the world to acknowledge the World Health Organisation (WHO) ruling that long-term night shift workers have a higher risk of developing breast cancer than those who work standard hours.

Denmark's government has already started paying compensation to women who developed breast cancer after years of working night shifts which is believed to cause disturbed sleep, fatigue and digestive problems, among a series of other health disorders.

The WHO is expected to release a report on a number of studies of shift workers in varying professions.