At some Danish workplaces, healthy employees are offered an influenza vaccination, although vaccination has not been proven to have a protective effect on healthy adults. This article gives an overview of the effect of influenza vaccination on healthy adults based on the results from the Cochrane review "Vaccines for preventing influenza in healthy adults" and new studies in the field of interest. These studies show a limited effect on influenza, influenza-like illness, lost workdays, physician visits and days of illness.