The number of Danes who suffer from mental illness during their lifetime is significantly higher than previously thought.

According to new research published by the University of Aarhus, a quarter of all Danes under the age of 50 have been treated for mental illness at some point in their lives, and that number increases to one in three moving into the next 50 years.

Previous estimates from the Danish Psychiatric Society had shown that just one in five Danes have been treated for mental illness during their lifetime.

Tip of the iceberg
The results from the latest study are based on admissions and treatment data in the public health system, and researchers say that they still may not give the whole picture.

“The numbers include only outpatient treatment and hospitalisation,” Ole Mors, one of the researchers, told Jyllands-Posten newspaper.

“This is only the tip of the iceberg, since many patients choose private treatment or never treat their mental disorder.”

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Anne Lindhardt, who heads the Danish Mental Health Foundation, said that despite the shortcomings, the new study paints a clearer picture of the extent of mental illness in Denmark.

“It provides a true picture of the extent of psychiatric problems in Denmark,” Lindhardt said.

“We hope that the study will help to prioritise the problem and equate mental illness with physical ailments like cancer.”