Body temperature: Difference between revisions

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*[[Hyperthyroidism]], the overproduction of [[thyroid hormone]]s, can cause [[heat intolerance]]
*[[Hyperthyroidism]], the overproduction of [[thyroid hormone]]s, can cause [[heat intolerance]]
*[[Hypothyroidism]], the underproduction or poor utilization of thyroid hormones, can cause [[cold intolerance]]
*[[Hypothyroidism]], the underproduction or poor utilization of thyroid hormones, can cause [[cold intolerance]]
*[[Anemia|Iron deficiency anemia]], both due to its effect on thyroid function and competing demands re: oxygenation versus decreases in blood flow to mitigate heat loss <ref>{{Cite journal|title=Iron and thermoregulation: a review|date=1996-12|url=https://pubmed.ncbi.nlm.nih.gov/8989508/|journal=Critical Reviews in Food Science and Nutrition|volume=36|issue=8|pages=747–763|last=Brigham|first=D.|last2=Beard|first2=J.|doi=10.1080/10408399609527748|pmid=8989508|issn=1040-8398}}</ref>
*[[Anemia|Iron deficiency anemia]], due to iron:
**iron's effect on thyroid function<ref name=":0" />
**competing demands re: oxygenation versus decreases in blood flow to mitigate heat loss<ref name=":0">{{Cite journal|title=Iron and thermoregulation: a review|date=1996-12|url=https://pubmed.ncbi.nlm.nih.gov/8989508/|journal=Critical Reviews in Food Science and Nutrition|volume=36|issue=8|pages=747–763|last=Brigham|first=D.|last2=Beard|first2=J.|doi=10.1080/10408399609527748|pmid=8989508|issn=1040-8398}}</ref>
**iron's status as a cofactor in many of the enzymes governing metabolic rate<ref>{{Cite journal|title=Iron, thermoregulation, and metabolic rate|date=1999-03|url=https://pubmed.ncbi.nlm.nih.gov/10198751/|journal=Critical Reviews in Food Science and Nutrition|volume=39|issue=2|pages=131–148|last=Rosenzweig|first=P. H.|last2=Volpe|first2=S. L.|doi=10.1080/10408399908500491|pmid=10198751|issn=1040-8398}}</ref>


==ME/CFS==
==ME/CFS==

Revision as of 17:45, May 27, 2022

The normal human body temperature range is typically stated as 36.5–37.5 °C (97.7–99.5 °F). The average internal temperature is 37.0 °C (98.6 °F). It is typically maintained within this range by thermoregulation. Body temperature normally fluctuates over the day following circadian rhythms, with the lowest levels around 4 a.m. and the highest in the late afternoon.

Core temperature is regulated and stabilized primarily by the hypothalamus, a region of the brain linking the endocrine system to the nervous system.

Pathophysiology[edit | edit source]

The following are diseases and disorders in which issues in thermoregulation may occur. Each may present in people with ME or ME/CFS.

ME/CFS[edit | edit source]

Temperature dysregulation[edit | edit source]

Temperature dysregulation, heat intolerance and cold intolerance are common symptoms of ME/CFS, and are is recognised in the Canadian Consensus Criteria as a neuroendocrine symptom.

  • 53.9% - 58.7% of the 2073 patients in a Belgian study of 2001 reported symptom exacerbation in extremes of temperature.[6]
  • Katrina Berne reports a prevalence of 75-80% for heat/cold intolerance.[7]

In the London criteria for ME, sensitivity to both heat and cold is mentioned under the criteria of periods of impaired circulation compatible with autonomic dysfunction.[8]

Temperature instability[edit | edit source]

Temperature instability and heat or cold intolerance are ME symptoms recognized in the International Consensus Criteria.[9]

Loss of thermostatic stability and intolerance of extremes of temperatures are separate diagnostic criteria in the International Consensus Criteria for ME. Indicators of temperature instability are listed as subnormal body temperature, marked fluctuations of temperature throughout the day; sweating episodes, recurrent feelings of feverishness with or without low grade fever, and cold extremities, e.g. fingers and toes.[9]

References[edit | edit source]

  1. Osilla, Eva V.; Marsidi, Jennifer L.; Sharma, Sandeep (2022). "Physiology, Temperature Regulation". Treasure Island (FL): StatPearls Publishing. PMID 29939615. Cite journal requires |journal= (help)
  2. Szelényi, Zoltán; Komoly, Sámuel (November 15, 2018). "Thermoregulation: From basic neuroscience to clinical neurology, part 2". Temperature: Multidisciplinary Biomedical Journal. 6 (1): 7–10. doi:10.1080/23328940.2018.1541680. ISSN 2332-8940. PMC 6422468.
  3. "Impaired Thermoregulation". PM&R KnowledgeNow. February 24, 2017. Retrieved May 27, 2022.
  4. 4.0 4.1 Brigham, D.; Beard, J. (1996-12). "Iron and thermoregulation: a review". Critical Reviews in Food Science and Nutrition. 36 (8): 747–763. doi:10.1080/10408399609527748. ISSN 1040-8398. PMID 8989508. Check date values in: |date= (help)
  5. Rosenzweig, P. H.; Volpe, S. L. (1999-03). "Iron, thermoregulation, and metabolic rate". Critical Reviews in Food Science and Nutrition. 39 (2): 131–148. doi:10.1080/10408399908500491. ISSN 1040-8398. PMID 10198751. Check date values in: |date= (help)
  6. De Becker, P; McGregor, N; De Meirleir, K (September 2001), "A definition-based analysis of symptoms in a large cohort of patients with chronic fatigue syndrome.", Journal of Internal Medicine, 250 (3): 234-240, PMID 11555128
  7. Berne, Katrina (December 1, 1995). Running on Empty: The Complete Guide to Chronic Fatigue Syndrome (CFIDS) (2nd ed.). Hunter House. p. 58. ISBN 978-0897931915.
  8. London Criteria (2014)
  9. 9.0 9.1 Carruthers, BM; van de Sande, MI; De Meirleir, KL; Klimas, NG; Broderick, G; Mitchell, T; Staines, D; Powles, ACP; Speight, N; Vallings, R; Bateman, L; Bell, DS; Carlo-Stella, N; Chia, J; Darragh, A; Gerken, A; Jo, D; Lewis, DP; Light, AR; Light, KC; Marshall-Gradisnik, S; McLaren-Howard, J; Mena, I; Miwa, K; Murovska, M; Stevens, SR (2012), Myalgic encephalomyelitis: Adult & Paediatric: International Consensus Primer for Medical Practitioners (PDF), ISBN 978-0-9739335-3-6