The police are more used to receiving saliva samples – both via a swab and airborne – so it must have made a pleasant change giving one on this occasion.

Some 73 Danish officers took part in tests that monitored their hormone levels on nightshifts, and Det Nationale Forskningscenter for Arbejdsmiljø, the national research centre for the work environment, can confirm what many of us already knew: working at night is bad for your health.

Three key hormones
The results reveal that nightshift officers see their levels of three key hormones – cortisol, testosterone and melatonin – severely depleted as they are secreted over the course of the night, majorly disrupting the body’s circadian rhythm.

And according to Anne Helene Garde, the project manager on the study, this affects their harmony in much the same way as the different sections of an orchestra complement one another.

Like an orchestra
“It’s like an orchestra that has lost its timing. The hormones are important for our body to function optimally,” she told DR.

“Most of those who work at night are tired and have difficulty sleeping enough. Some have problems with their stomachs and others with their cheeriness.”