Now, researchers are warning of a phenomenon called \u201cinternal jet lag.\u201d A startling examination<\/a> of young Australians who sought mental health treatment revealed that some of these patients appeared to have jet lag symptoms \u2014 even though they didn\u2019t travel.<\/p>\n Jet lag is when a person\u2019s internal biological clock, also known as their circadian rhythm, isn\u2019t aligned with the new time zone after flying. EdNurg \u2013 stock.adobe.com<\/p>\n \u201cWe analyzed participants\u2019 core body temperature, cortisol levels<\/a> and melatonin levels<\/a>, which we know play important roles in how our bodies manage the circadian rhythm \u2014 our 24-hour cycles \u2014 which regulate things like wakefulness and sleep,\u201d said Joanne Carpenter of the University of Sydney.<\/p>\n \u201cWhen we looked at these three measures in\u00a0young people\u00a0who presented to\u00a0mental health services, we found that 23% of patients were experiencing a kind of physiological jet lag.\u201d<\/p>\n The peculiar findings suggest that healthcare providers should target biological clocks when treating mood disorders.<\/p>\n Mood disorders can be characterized by persistent sadness (depression), extreme happiness (mania) or a combination of both (bipolar disorder<\/a>).<\/p>\n \u201cInternal jet lag\u201d is when biological \u201cclocks are not just delayed but not lining up with each other.\u201d It could be linked to mental health disorders. Marco \u2013 stock.adobe.com<\/p>\n The new study featured two sets of participants. The first group were 69 people aged 16 to 35 who visited a mental health clinic in Sydney.<\/p>\n The other group of 19 young people didn\u2019t have a history of mental illness.<\/p>\n The participants swallowed a sensor that continuously logged their body temperature. The researchers also measured their sleep and the circadian-related hormones melatonin and cortisol.<\/p>\n Your body naturally produces melatonin, which helps regulate the sleep-wake cycle by signaling that it\u2019s time for bed.<\/p>\n Cortisol, meanwhile, prepares the body for activity upon waking.<\/p>\n \u201cWe were able to measure melatonin and\u00a0cortisol levels\u00a0using saliva samples in the lead up to sleep and after participants woke,\u201d Carpenter said.<\/p>\n \u201c[This] is the first time these key markers of the circadian rhythm have been combined with body temperature to study how circadian rhythms might be misaligned in people with mood disorders.\u201d<\/p>\n This graphic from the study shows correlations between circadian measures and depressive symptoms in youth with emerging mood disorders. sagepub<\/p>\n Carpenter\u2019s team found that at least two of these circadian rhythm measures were out of sync in 23% of the mental health patients.<\/p>\n She described \u201cinternal jet lag\u201d as when the \u201cclocks are not just delayed but not lining up with each other.\u201d<\/p>\n \u201cWhile we do see teenagers sleeping later because of normal developmental shifts in the body clock to later timing across adolescence, what we are seeing here is a more extreme kind of circadian disruption,\u201d Carpenter explained.<\/p>\n \u201cThis is similar to the disruption we see when traveling across\u00a0time zones\u00a0or undertaking shift work<\/a>, when the body clock becomes out of sync with the external environment,\u201d she added.<\/p>\n![\"Jet](\"https:\/\/www.newsbeep.com\/au\/wp-content\/uploads\/2025\/07\/9c476a8d2d22ba8d9f9161ad8812a74f.jpeg\"\/)
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