from the world's big
Getting a good night's sleep just took on a whole new meaning.
- A new study introduces a new method for determining your personal circadian rhythm.
- This could have profound effects on combating cognitive disorders and helping patients understand when to take medicine.
- The blood test measures a person's biological clock to within 1.5 hours.
Photo: Yuris Alhumaydy / Unsplash<p>The human circadian rhythm approximates with the rising and setting of the sun, though that's not the final word in this story. Before electric lights we slept in <a href="https://www.sciencealert.com/humans-used-to-sleep-in-two-shifts-maybe-we-should-again" target="_blank">two shifts</a> — still within the timeframe of the rotation of the planet, however. As Daniel Pink writes in <em>When</em>, his book on timing, there is individual variation in this rhythm: 14 percent of humans are what he terms "larks" and 21 percent "night owls," while the majority are "third birds," meaning their midpoint of sleep is between 3–4 am.</p><p>How do you know what feathered vertebrate you are? It turns out your blood can tell you. A new test called TimeSignature, announced in a <a href="http://www.pnas.org/content/early/2018/09/05/1800314115" target="_blank">study</a> published in the <em>Proceedings of the National Academy of Sciences</em>, requires only two blood draws to inform you what your genes say about your circadian rhythms. </p><p>This follows previous, expensive tests requiring numerous blood draws at specific times of the day. TimeSignature measures forty different gene expression markers that signal when you should be sleeping. Though variation might exist dependent upon scheduling — I remember gruelingly working overnight shifts in the emergency room back in college — your genetic make-up doesn't lie. </p><p>Now we can pinpoint the hours we should be unconscious with previously unavailable precision. <a href="https://www.futurity.org/circadian-rhythm-blood-test-1865492-2/" target="_blank">According to</a> Northwestern University Feinberg School of Medicine assistant professor (and lead author of the study), Rosemary Braun,</p><blockquote>This is a much more precise and sophisticated measurement than identifying whether you are a morning lark or a night owl. We can assess a person's biological clock to within 1.5 hours.</blockquote>
They proved how the biological mechanism works inside our cells.
The Nobel Prize for Physiology (or Medicine) was announced on Oct. 2 in Sweden. Three American scientists jointly took home this prestigious award for their work on circadian rhythms. This is the biological clock all organisms have which controls our sleep-wake cycle, the release of hormones at important intervals, body temperature, blood pressure, and other critical mechanisms, in order to maintain homeostasis or balance.
A "new" field of medicine called chronotherapy demonstrates that following nature's cycles, as our ancestors did, is integral to proper biological and cognitive function.