Factors influencing body temperature

Discuss about the Body Temperature for Human Thermoregulation and Measurement.

Humans have adapted to the life on earth for more than 300 000 years. Reason being, the earth atmosphere provide us with air, water, food which are the basic requirements for human survival but does not guarantee 100% survival. However, it is also important to consider that temperature also plays a very vital role in human survival and for our body to achieve thermal comfort, the temperature should always be within a certain range. A person’s body temperature is influenced by, gender, age, infection, work that is done and reproductive status, the period when the measurement is taken, part of the body at which measurement is taken, individuals state ( sleeping, sedated or walking) and their emotional state. An individual’s body temperature is of concern in human reproduction, sports events, and therapeutic practice (Lupton 2012).

The average body temperature of a fit adult is 98.60 Fahrenheit or 37.00 Celsius (Gomez, 2014). It is usually retained at this level by thermoregulation. However, an individuals’ normal temperature may fluctuate during the day as regulated by their circadian rhythm. Moreover, body temperatures may vary depending on a persons’ metabolism rate. The slower it is the lower the body temperature or the faster it is the higher the normal human body temperature. Other external factors may cause fluctuations in the normal human body temperature. Normal body temperature tends to be high at night due to food intake and muscular day activity and low at daytime because of the rest experienced after sleeping. Temperature-normal should be maintained at 37.00 C to guarantee a healthy individual state (Jurkovich, 2007). Body temperatures above normal denote a fever and these calls for a checkup.

 Body temperature measurements vary depending on the part of the body being measured (Niedermann et.al 2014). Oral (mouth) temperatures are the most convenient method of obtaining temperature readings and they range at 37.00 C. Axillary body temperatures, taken amongst two folds of skin on the body or the armpit, are an external form of temperature measurement. It is time-consuming and the most imprecise method since temperatures falls at 36.40 C or 97.60 F (Kreitzman and Foster, 2011). Rectal body temperatures taken in the rectum is an internal method of temperature measurement. It is the shortest and most precise method of temperature measurement since it is taken internally. Every method of temperature measurement has different regular ranges dependent on the gender of an individual (Lim 2008).

Methods of measuring body temperature

Human body produce energy during metabolism processes where one type of energy is converted to another within the body. Metabolism involves chemical reactions that either produce or consume energy. Catabolism is the category of metabolism that leads to energy production through the breakdown of chemically bound molecules since it is an exergonic reaction (Lim et al., 2008). Chemical energy within the body can either be converted to thermal energy during digestion since the body generates heat during digestion or to mechanical energy in a muscle movement form (Mekjavic 2006). Our bodies regulate heat via thermoregulation, the ability of the body to maintain the normal body temperature despite the different temperature levels within the surrounding, in various mechanisms which include sweating this mainly occurs when our bodies lose water (evaporation) resulting to heat loss from the body (Lupton, 2012). Evaporation is mainly influenced by air humidity, the less the humid amount the more effective evaporation will be at heat loss since it will be easier to convert sweat into vapor as the air has less water in it (Tansey 2015). Radiation transfer of internal energy in electromagnetic waves forms a normally infrared radiation. Heat loss from our bodies may be associated with the heat from a fire. If one stands in the light produced by the fire they get warmer, than if something was blocking this light as it would prevent the radiated heat from reaching you. The human body, however, to a slighter degree than fire, emits heat into the surrounding in order to lose heat. Our bodies also gain radiated heat from the sun if we are working from outside. Vasodilation occurs when the blood vessels under the skin widen resulting to an increase in blood flow to the skin where it is cooler away from the warm interior body thus allowing the body to release heat via radiation (Mekjavic and Eiken, 2006). Shivering it involves the rapid contraction and relaxation of skeletal muscles and it results in heat production via respiration. Vasoconstriction results when the blood vessels become smaller thus reducing the blood flow to the skin keeping the inner body warm (Jessen 2012).

Homeostasis is maintenance of a constant internal surrounding in response to a change in the external surrounding. Maintain metabolism, is crucial to the maintaining of the normal temperature. Thermo receptors in the skin and the hypothalamus in the brain help in detecting the body temperature in mammals (Niedermann et al., 2014). For instance, increase in temperature will send a message to the hypothalamus via sensory neurons, which then interprets the signals and secretes a hormone that is carried to the sweat glands via blood (Roepke et al., 2012). This causes nerve impulses from the brain to activate the sweat glands to secrete sweat hence emitting heat and decreasing the body temperature to normal (Roepke et al 2010). 

Consequences of temperature fluctuations

Despite the ability of our bodies to maintain normal body temperatures, some surrounding extremes, infection or injury and irregular endocrine function may result to the failure of the organism to preserve normal body temperature within the desired range. In most cases, this leads into major functional disorders like hypothermia it occurs when the body heat is lost and the core temperature is too low either due to injury or due to exposure to cold (Jurkovich 2007). Hypothermia resulting from cold exposure can be fatal but with help of modern therapeutic care, it can be treated. Hypothermia effects are profound in patients with injury since hypothermia is a major component of the ‘’bloody vicious cycle’’. Frostbite it occurs when the skin freezes and loses blood flow. It can leave permanent damage if not realized early (Tansey and Johnson, 2015). An uncovered skin may die and turn black leaving irreparable injury to the nerves and tissues.

It is an abnormal rise in body temperature initiated by the failure of the normal heat-regulating mechanisms resulting in heat; stroke, syncope, fatigue, cramps and exhaustion (Gomez 2014). It can also be referred to as an increase in the body temperature because of failed thermoregulation that occurs when the body takes in more heat than is required (Niedermann et al., 2014). This condition becomes a medical emergency that needs serious attention to prevent death or disability.

 The main causes of hyperthermia include stroke and extreme drug reactions. The other form of acute temperature rise is caused by exposure to excessive heat that surpasses the heating regulation mechanism in the body (Niedermann et al., 2014). The latter is a rare side effect of many drugs especially those that affect the nervous system. Hyperthermia is different from fever in that the human body temperature remains unchanged (Niedermann et al., 2014). The opposite of this situation is hypothermia, which occurs when the body temperature falls below the required level for normal metabolism.

Conclusion

Temperature is significant for the maintenance of a good healthy life. For that reason, it is important for individuals to ensure that they familiarize themselves with the current temperature state of their surroundings to help maintain their normal body temperature so as to avoid any temperature related disorders. Therefore, individuals should ensure that they lead lives that will enable their bodies to conduct normal biological processes to avoid any health issues that may alter the normal body temperature (Kreitzman 2011).

References

Gomez, C.R., 2014. Disorders of body temperature. In Handbook of clinical neurology (Vol. 120, pp. 947-957). Elsevier.

Jessen, C., 2012. Temperature regulation in humans and other mammals. Springer Science & Business Media.

Jurkovich, G.J., 2007. Environmental cold-induced injury. Surgical Clinics, 87(1), pp.247-267.

Kreitzman, L. and Foster, R., 2011. The rhythms of life: The biological clocks that control the daily lives of every living thing. Profile books.

Lupton, D., 2012. Medicine as culture: Illness, disease and the body. Sage.

Lim, C.L., Byrne, C. and Lee, J.K., 2008. Human thermoregulation and measurement of body temperature in exercise and clinical settings. Annals Academy of Medicine Singapore, 37(4), p.347.

Mekjavic, I.B. and Eiken, O., 2006. Contribution of thermal and nonthermal factors to the regulation of body temperature in humans. Journal of applied physiology, 100(6), pp.2065-2072.

Niedermann, R., Wyss, E., Annaheim, S., Psikuta, A., Davey, S. and Rossi, R.M., 2014. Prediction of human core body temperature using non-invasive measurement methods. International journal of biometeorology, 58(1), pp.7-15.

Roepke, T.A., Bosch, M.A., Rick, E.A., Lee, B., Wagner, E.J., Seidlova-Wuttke, D., Wuttke, W., Scanlan, T.S., Rønnekleiv, O.K. and Kelly, M.J., 2010. Contribution of a membrane estrogen receptor to the estrogenic regulation of body temperature and energy homeostasis. Endocrinology, 151(10), pp.4926-4937.

Tansey, E.A. and Johnson, C.D., 2015. Recent advances in thermoregulation. Advances in physiology education, 39(3), pp.139-148.