The study, which includes figures on sick days taken by the 4.1 million members of health insurer Techniker Krankenkasse in 2013, shows huge differences between careers and regions of the country. The highest illness rates are in the states of the former communist East Germany.
Metal workers in the eastern state of Mecklenburg Western-Pomerania, for example, were most likely to take time off ill, while office workers in the south-west, were the least sickly employees, the study found.
Workers in the north-east of Germany are the sickliest, with an average of 18.4 days off a year in Mecklenburg Western-Pommerania.
This figure was closely followed by neighbouring Brandenburg, where the average worker took 18.1 days off last year.
Employees in the south-west of the country, by contrast, needed the fewest number of sick days - 12.1 days per worker in Baden-Württemberg and 12.5 in Bavaria.
Office workers were the least sickly of all the professions examined, whereas metal workers, construction workers, warehouse employees and drivers took the highest number of time off for illness.
The study also showed a gender divide when it comes to sick leave, with men taking fewer days off than women on average - 12.9 days as opposed to 15.9 for their female counterparts.
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