Human Seasonal Rhythms: Circadian Clocks
- Despite modern conveniences like electric lights, human circadian rhythms still respond to seasonal changes in daylight, according to new research.
- Ruby Kim, a postdoctoral assistant professor of mathematics at the University of Michigan, said humans are more seasonal than they might realise.
- The findings, published in npj Digital Medicine, could provide new insights into seasonal affective disorder and other health issues related to circadian rythm alignment.
Human circadian rhythms,the body’s internal clocks,are profoundly influenced by seasonal daylight changes,a new study reveals. This research highlights how our internal biological systems are intrinsically linked to sunlight, impacting sleep, emotional state, and even cardiovascular health. Ruby Kim, a postdoctoral assistant professor, emphasizes the significant role of day length on our physiology, influencing daily schedules despite modern lighting. This understanding could enhance our insights into seasonal affective disorder and related health issues stemming from circadian rhythm alignment.The research also uncovers genetic elements which might explain why some individuals adapt to changing daylight patterns more easily than others.News Directory 3 is constantly reporting on groundbreaking health discoveries. The study points to two internal clocks that are critical to the body’s response. Discover what’s next for the future of these discoveries…
Human circadian Rhythms Track Seasonal Daylight Changes
Despite modern conveniences like electric lights, human circadian rhythms still respond to seasonal changes in daylight, according to new research. The study suggests that our internal clocks are hardwired to track the amount of sunlight, influencing sleep schedules and potentially affecting mental and cardiovascular health.
Ruby Kim, a postdoctoral assistant professor of mathematics at the University of Michigan, said humans are more seasonal than they might realise. Kim noted that day length significantly impacts human physiology, affecting how people adjust to daily schedule changes.
The findings, published in npj Digital Medicine, could provide new insights into seasonal affective disorder and other health issues related to circadian rythm alignment. Daniel Forger, professor of math and director of the Michigan Center for Applied and Interdisciplinary Mathematics, previously demonstrated the strong connection between mood and sleep schedule alignment with circadian rhythms.
Kim believes the research holds promise for future discoveries, potentially impacting mental health conditions like mood and anxiety, and also metabolic and cardiovascular health.
The study also revealed a genetic component to this seasonality, which may explain why some individuals adapt more easily to changes in day length than others. Forger said that understanding this genetic aspect could help doctors identify individuals who are more vulnerable to disruptions caused by seasonal changes.
Forger added that many people think of circadian rhythms as a single clock, but the research indicates there are two clocks: one tracking dawn and the other tracking dusk, and they communicate with each other.
Researchers analyzed sleep data from thousands of medical residents using wearable health devices as part of the Intern Health Study, funded by the National Institutes of Health. Thes interns, whose shift work often disrupts their sleep schedules, provided valuable data on how circadian rhythms respond to seasonal changes.
The fact that circadian rhythms in this population exhibited seasonal dependence suggests this feature is deeply ingrained in humans.Forger noted that studies on fruit flies and rodents have shown similar seasonal circadian clocks, and this new research provides strong support for the idea in humans.
The Intern Health Study also included DNA testing, allowing Kim and Forger’s team to identify a gene variation that made shift work more disruptive to circadian clock alignment in a small percentage of interns.
What’s next
Researchers plan to further explore the health implications of these findings, particularly the influence of shift work on individuals with different genetic predispositions.