Shift workers make quite a demand on their bodies. To be and remain efficient, they have to take special care of themselves. Does irregular food intake have negative consequences for their health?
When night becomes day
Shift workers, especially night shift workers, are subject to special stresses in terms of health and performance. Irregular working hours at changing times of the day can be experienced as stress by the body and psyche, and in the long term can be associated with numerous complaints: Sleep problems, fatigue, reduced performance, loss of appetite, diseases of the gastrointestinal tract or the cardiovascular system.
In time – the internal clock
The bodily functions of humans, like those of most animals, are subject to a daily and nightly rhythm. The clock for this is the “internal clock,” a small nerve nucleus in the brain that controls our biorhythms and responds to light. The readiness to perform is normally highest during the day, although there are also fluctuations with small performance lows. At night, the organism switches back to economy mode and refuels. The pulse rate and blood pressure drop, and fewer digestive secretions are produced; on the other hand, liver performance and the need for warmth, for example, are increased.
Nocturnal meals – a problem?
Working against the biological rhythm, i.e. shift work, means for the body that the required performance in the evening and during the night must be as high as for daytime workers. The rhythm of the human organism is controlled from the brain and is closely linked to light stimuli on the eyes. Researchers have discovered that in addition to this central pacemaker, there are similar effects from various other body tissues (e.g., in the liver) – at least in mice.
If a typical day-night rhythm is suggested to the body by the ambient brightness, its central pacemaker adjusts the rhythm – for example, it succeeds in setting us to a different rhythm when we travel long distances. Food, on the other hand, seems to have little effect on the brain‘s internal clock; only the peripheral clocks respond. This means that the body can release digestive enzymes, for example, when food is consumed “out of time,” without this directly throwing its day-night rhythm out of sync. Reassuring, because otherwise night workers would have to set an alarm clock to eat during the day.
