A woman clothed in a warm parka dumps hot water onto a naked man during a Fairbanks winter in below freezing temperatures.


Taking a walk in the sub-zero temperatures of Fairbanks can naturally raise your core body temperature by simply cutting down on the amount of clothing you wear. It is as simple a concept of how a hot shower cools you down before going to bed at night.

Negative feedback loops create homeostasis within the body, which is the overall physiological function of bringing the body back down or up to normal levels. Body temperature is an excellent example of this because metabolic processes cannot function properly at too high or too cold of temperatures. This is called thermoregulation, which is controlled by the hypothalamus in the brain sensing if the body is too hot or too cold (Osilla, et al., 2021). The connection between thermoregulation and metabolism is strong, for if the body is too cold or hot the circulatory system becomes susceptible to vasoconstriction. This is important to understand because the circulatory system is involved in very important processes such as cellular respiration and blood flow from and to the heart. With low body temperature vasoconstriction causes loss of blood flow to the outer extremities, and if too high can cause heat stroke (Alba, et al., 2019). This background information brings the drawing I have done for my Steam project to point, because using these forms of hot and cold vasoconstriction can have a positive effect on the body when it comes to creating homeostasis with negative feedback loops.

               The drawing here depicts a man sitting outside in below freezing temperatures naked while a woman pours hot water on him. One may find this insane, but this drawing shows the ancient naturopathic practice of constitutional hydrotherapy, which is a form of raising the body’s core temperature by using rapid, internal (or external) exchanges of hot and cold water (Mooventhan & Nibethitha, 2014). Although an ancient method, it is still used today in naturopathic and Chinese practices to raise or lower a patient’s core body temperature. I used to perform this practice with a Naturopathic doctor that I worked with here in Fairbanks, Alaska. Traditionally, patients were submerged and switched between tubs of very hot or cold water. Nowadays they are placed on a bed naked and wrapped in wool blankets, as wool does not absorb water. Hot and cold towels are placed on the bare skin intermittently under the wrapping for about 25-40 minutes. Body temperature is taken before and after the treatment, and depending on if cold or hot towels were started first the body temperature should lower or raise. Normal body temperature should be around 98.6 degrees Fahrenheit, and I have personal testimonials of patients raising from 97.5 to 98.4 degrees Fahrenheit.

               When the body is running below or above its normal temperature it is constantly under the pressure of vasoconstriction, contributing to many circulatory system diseases such as high and low blood pressure. The North American Journal of Medical Sciences states that “in patients with chronic heart failure (CHF) thermal vasodilatation following warm-water bathing and low-temperature sauna bathing (LTSB) at 60°C for 15 min improves cardiac function” (Mooventhan, A. & Nibethitha L., 2014). This is another clinical example of how using water with temperature change affects an increase in metabolic function. Although the man in my photo is not submerged in water, I find this concept and practice very interesting because snow and ice are water that is frozen. It creates a freezing environment that we live in every winter here in Fairbanks, Alaska. A lower- or higher-than-normal body temperature can cause fatigue in us on a daily basis because our bodies are not functioning at optimal level. Using this natural negative feedback loop with body temperature to create homeostasis can be an optimal form of gaining energy back and lowering the risk of disease caused by a dysfunctional metabolic system.


Alba, BK., Castellani, JW., Charkoudian, N. (2019). Cold-induced cutaneous vasoconstriction in humans: Function, dysfunction and the distinctly counterproductive. Experimental Physiology (104), 1202–1214.

Mooventhan, A., & Nivethitha, L. (2014). Scientific evidence-based effects of hydrotherapy on various systems of the body. North American Journal of Medical Sciences, 6(5), 199. https://doi.org/10.4103/1947-2714.132935

Osilla, EV., Marsidi, JL., Sharma, S. (2021). Physiology, Temperature Regulation. [Updated 2021 May 7]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan. Available from: https://www.ncbi.nlm.nih.gov/books/NBK507838/

One Comment

  1. After taking a look at the painting I was having a difficult time making the connection. This is due to the fact that I would find it very hard to believe that throwing hot water on someone that is suffering from hypothermia in the dead of Alaskan winter would be the best idea to help them. Due to the fact that it could possibly damage their skin and also warming them too fast could be damaging to the cardiovascular system. Then I read the abstract and decided to do a little research on constitutional therapy using the links provided; I learned a lot about alternative methods that could help regulate one’s body temperature in order to help with such things like diseases and metabolism. ” The most effective method of reducing body core temperature appears to be immersion in iced water, main predictor of outcome in exertional heatstroke is the duration and degree of hyperthermia where possible patients should be cooled using iced-WI, but if it is not possible, combination of other techniques may be used to facilitate rapid cooling[94] such as fan-therapy, CWI, iced-baths, and evaporative cooling” (Mooventhan and Nibethitha, 2014).
    This all can be tied into the negative feedback loop of thermoregulation as mentioned by Kristina; which is how the body regulates it temperature. If the body temperature is too high the hypothalamus sends a signal to either increase the blood circulation to the body’s surface to start sweating. This could help cool the body down the body temperature. Likewise if body temperature gets too low it the hypothalamus can initiate the process for us to start shivering to produce more heat. This is why this is a negative feedback system because the further the body temperature goes away from the ideal temperature (between 97.7 to 99.5 degree Fahrenheit) temperature receptors in the hypothalamus stimulate heat-producing mechanism to help it to return to homeostasis.

    Mooventhan, A., & Nivethitha, L. (2014). Scientific evidence-based effects of hydrotherapy on various systems of the body. North American journal of medical sciences, 6(5), 199–209. https://doi.org/10.4103/1947-2714.132935

    Betts, J. G, Desaix., Johnson, E., Johnson, J., Korol, O., Kruse, D., Poe, B. Wise, J., Womble, M., & Young, K. (2017). Anatomy & physiology. Openstax College, Rice University.

    Trika Henry

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