Editing Jet lag (section)

== Health effects of chronic jet lag ==

=== Mental health implications ===
Jet lag may affect the mental health of vulnerable individuals. When travelling across time zones, there is a "phase-shift of body temperature, rapid-eye-movement sleep, melatonin production, and other circadian rhythms".<ref name="young">{{cite journal |last1=Young |first1=D. M. |year=1995 |title=Psychiatric morbidity in travelers to Honolulu, Hawaii |journal=Comprehensive Psychiatry |volume=36 |issue=3 |pages=224–228 |doi=10.1016/0010-440x(95)90086-b |pmid=7648847}}</ref> A 2002 study found that relapse of [[Bipolar disorder|bipolar]] and [[psychotic disorders]] occurred more frequently when seven or more time zones had been crossed in the past week than when three or fewer had been crossed.<ref name="katz">{{cite journal |last1=Katz |first1=G. |last2=Knobler |first2=H. Y. |last3=Laibel |first3=Z. |last4=Strauss |first4=Z. |last5=Durst |first5=R. |year=2002 |title=Time zone change and major psychiatric morbidity: the results of a 6-year study in Jerusalem |journal=Comprehensive Psychiatry |volume=43 |issue=1 |pages=37–40 |doi=10.1053/comp.2002.29849 |pmid=11788917}}</ref> Although significant circadian rhythm disruption has been documented as affecting individuals with bipolar disorder, an Australian team studied suicide statistics from 1971 to 2001 to determine whether the one-hour shifts involved in daylight saving time had an effect. They found increased incidence of male suicide after the commencement of daylight saving time but not after returning to standard time.<ref>{{cite journal |last1=Berk |first1=Michael |last2=Dodd |first2=Seetal |last3=Hallam |first3=Karen |last4=Berk |first4=Lesley |last5=Gleeson |first5=John |last6=Henry |first6=Margaret |date=January 2008 |title=Small shifts in diurnal rhythms are associated with an increase in suicide: The effect of daylight saving |journal=Sleep and Biological Rhythms |volume=6 |issue=1 |pages=22–25 |doi=10.1111/j.1479-8425.2007.00331.x}}</ref>

=== Obesity and type 2 Diabetes ===
Constant disruption caused by chronic jet lag can cause complications to the daily metabolic cycle of an individual due to a hinted link between circadian rhythm and [[Metabolism|metabolic]]/epigenetic mechanisms.<ref>{{cite journal |last1=Stenvers |first1=Dirk Jan |last2=Scheer |first2=Frank A. J. L. |last3=Schrauwen |first3=Patrick |last4=la Fleur |first4=Susanne E. |last5=Kalsbeek |first5=Andries |title=Circadian clocks and insulin resistance |journal=Nature Reviews Endocrinology |date=February 2019 |volume=15 |issue=2 |pages=75–89 |doi=10.1038/s41574-018-0122-1 |pmid=30531917 |url=https://cris.maastrichtuniversity.nl/en/publications/f3ec1de0-8a94-4aac-b6f8-ec8d96e82b5b |hdl=20.500.11755/fdb8d77a-70e3-4ab7-a041-20b2303b418b |hdl-access=free }}</ref> This is due to the process of food intake acting as a [[Zeitgeber]] towards the circadian mechanisms and their control on the metabolic systems. The multiple disruptions of the circadian clock due to chronic jet lag alter eating habits causing irregular eating times, over/under eating, and metabolic inconsistencies that lead to a higher risk of [[type 2 diabetes]] and obesity.<ref>{{cite journal |last1=Sato |first1=Tomoki |last2=Sato |first2=Shogo |title=Circadian Regulation of Metabolism: Commitment to Health and Diseases |journal=Endocrinology |date=6 June 2023 |volume=164 |issue=7 |doi=10.1210/endocr/bqad086 |pmid=37253106 }}</ref>

=== Cancer ===
Research on animal models have shown that [[cancer]] growth has a potential link to chronic jet lag's effect on the circadian rhythm due to constant disruption. This is due to the nature of jet lag's ability to disturb molecular structures clocks and that include cells within the body. The circadian rhythm regulates the pace of cell processes such as decay and growth, and a disturbance towards the circadian rhythm is theorized to insight tumor growth.<ref>{{Cite journal |last1=Khan |first1=Suliman |last2=Xue |first2=Mengzhou |last3=Yong |first3=V. Wee |date=2021-09-28 |title=Does chronic jet lag increase risk of cancer? |journal=Aging |volume=13 |issue=18 |pages=21810–21811 |doi=10.18632/aging.203596 |issn=1945-4589 |pmc=8507272 |pmid=34586082}}</ref> This is even of more concerned for scientist when looking at immune cells which are told to be heavily dependent on its molecular clock and now risk tumor growth and decrease functionality due to chronic jet lag.<ref>{{Cite journal |last1=Zeng |first1=Yuen |last2=Guo |first2=Zichan |last3=Wu |first3=Mengqi |last4=Chen |first4=Fulin |last5=Chen |first5=Lihua |date=2024-04-27 |title=Circadian rhythm regulates the function of immune cells and participates in the development of tumors |journal=Cell Death Discovery |language=en |volume=10 |issue=1 |page=199 |doi=10.1038/s41420-024-01960-1 |pmid=38678017 |pmc=11055927 |issn=2058-7716}}</ref>

=== Chronic inflammation ===
Recent studies have demonstrated the delicate balance that circadian rhythm provides towards gut-microbiome. Chronic circadian rhythm disruption introduces a variety of disturbances within the gut that can potentially cause a multitude of issues such as inflammation. This is due to, what researchers call, a misalignment of regulatory clocks that control metabolic processes that spike [[insulin]] levels when there's an irregular timing of food intake causing inflammation.<ref>{{cite journal |last1=Crespo |first1=Manuel Tomás |last2=Trebucq |first2=Laura Lucía |last3=Senna |first3=Camila Agustina |last4=Hokama |first4=Guido |last5=Paladino |first5=Natalia |last6=Agostino |first6=Patricia Verónica |last7=Chiesa |first7=Juan José |title=Circadian disruption of feeding-fasting rhythm and its consequences for metabolic, immune, cancer, and cognitive processes |journal=Biomedical Journal |date=January 2025 |pages=100827 |doi=10.1016/j.bj.2025.100827 |pmid=39756653 |doi-access=free }}</ref> Researchers have longed believed in the correlation of proper circadian balance, the disruption of the balance and its side effects, and metabolism though more research is needed to understand underlying mechanisms.<ref>{{cite journal |last1=Woller |first1=Aurore |last2=Gonze |first2=Didier |title=Circadian Misalignment and Metabolic Disorders: A Story of Twisted Clocks |journal=Biology |date=10 March 2021 |volume=10 |issue=3 |pages=207 |doi=10.3390/biology10030207 |doi-access=free |pmc=8001388 |pmid=33801795 }}</ref>