Are there local maximum values ​​for the body temperature

What is fever

Fever is an increase in body temperature above the naturally set "target" temperature. Fever is a symptom, not an independent disease. It can occur in a number of different clinical pictures. Since the body temperature fluctuates even in healthy people (see below), If one speaks of fever only above certain limit values: Measured orally (ie in the mouth) means an increase in body temperature to over 37.8 degrees Celsius (° C), measured rectally (ie in the anus) only from 38.2 ° C.

The body temperature is usually around 37 ° C, which means the core body temperature, i.e. the temperature inside. Certain areas of the body, for example the chest or the brain, are warmer than other regions of the body. In the thighs and upper arms the temperature is only between 34 and 36 ° C, in the feet and hands it is even cooler with an average of 28 ° C. When measuring body temperature, it is therefore always important to name the location of the measurement. The axillary measurement (i.e. in the armpit) is very unreliable. If the body temperature deviates significantly from the normal value, this can result in tissue and organ damage. A temperature of more than 42.6 ° C is usually fatal.

Time of day fluctuations

Body temperature depends on various factors and is therefore never completely constant. The temperature fluctuates over the course of a day: In the morning, an average of 36.2 ° C is measured orally (36.0 ° C axillary and 36.5 ° C rectal). Over the course of a day, the temperature rises by up to 1 ° C to around 37.5 ° C orally. (37.2 ° C axillary, 37.8 ° C rectal). Physical activity can warm the body by around 2 ° C. Even an opulent meal can "heat up" the body. In women, the body temperature rises in the 2nd half of the cycle, i.e. after ovulation until the next menstrual period, by around 0.5 ° C. However, the body temperature does not normally rise above 37 8 ° C.

MeasurementBody temperature Fluctuations
Oral (mouth) 37 ° C 35.5 to 37.5 ° C
Axillary (armpit)36.5 ° C 34.7 to 37.3 ° C
Rectal (anus)37.8 ° C 36.6 to 38.0 ° C
Auricular (ear)37.5 ° C35.8 to 38.0 ° C

Fever in the elderly

Older people sometimes have a slightly lower body temperature than younger people. Infection very often proceeds with no signs of fever in old age. Around 20 to 50% of older people react differently to an acute infection than when they were young: They have fewer or hardly any specific complaints that indicate a specific infection, but often unspecific general symptoms such as loss of appetite, increased tiredness or restlessness and fatigue. In a great many cases, those affected are mentally confused. These atypical symptoms are particularly dangerous because infections can easily be overlooked if they do not cause a "real" fever.