Katie Sharkey: favor circadian timing
- Healio published a May 1 Q&A with Wake Forest sleep specialist Katie Sharkey arguing that sleep timing — not just sleep hours — shapes sleep health. - Sharkey said circadian rhythm disorders happen when the body’s internal clock and the outside world drift apart, leaving sleep normal only at the “wrong” time. - That matters because sleep medicine is shifting past hours-slept alone toward timing, regularity, and treatment for clock-driven disorders.
Sleep advice usually gets flattened into one number — get 7 to 9 hours and you’re done. But that leaves out the part that often decides whether sleep comes easily, feels restorative, or keeps colliding with work and school. The missing piece is timing. In a May 1 explainer, Katie Sharkey at Wake Forest made the case that your circadian clock — the internal system that tells your body when to feel sleepy and when to feel alert — matters just as much as the raw total. (healio.com) ### Who is Katie Sharkey? Sharkey is a sleep medicine physician and professor at Wake Forest University School of Medicine, where she leads the Center for Sleep and Circadian Rhythms. That matters because this is not generic wellness talk — it is coming from someone who treats both insomnia and circadian rhythm disorders in clinical practice. (schoo([healio.com)our body has internal clocks that run on a roughly 24-hour cycle. They help time sleep, alertness, hormones, metabolism, and even parts of immune function. Light is the big cue — especially morning light — and when those signals line up with daily life, sleep tends to feel more stable. When they do not, the body can be ready for sleep at a time your schedule refuses to allow. (nhlbi.nih.gov) ### Why isn’t total sleep enough? Because “healthy sleep” is bigger than duration. The American Academy of Sleep Medicine frames healthy sleep as duration plus quality, timing, regularity, and the absence of disorders. You can technically get enough hours but still feel awful if those hours land at a biologically misaligned time, or if your schedule keeps jerking your clock around. Basically, sleep is not just a quantity problem. It is also a timing problem. (aasm.org) ### What goes wrong when timing slips? Circadian rhythm sleep-wake disorders show up when your internal clock falls out of sync with the environment. The classic example is delayed sleep-wake phase disorder — someone naturally gets sleepy much later than expected, often by 2 hours or more, and then struggles with early obligations. The key point is that sleep itself may be no(aasm.org). (nhlbi.nih.gov) ### Is this just about night owls? Not at all. Shift work, jet lag, advanced sleep timing, irregular sleep-wake patterns, and non-24-hour rhythms can all push the clock off course. Modern life makes this easier than ever — bright light at night, inconsistent bedtimes, and work schedules that ask the body to be alert when biology wants darkness and sleep. That mismatch is the whole story. (n([nhlbi.nih.gov)s)) ### Why does that mismatch matter? Because poor sleep is not only about feeling groggy. Sharkey’s May 1 piece tied inadequate sleep to cardiovascular disease, diabetes, obesity, depression, anxiety, accidents, and lower productivity. Federal public-health goals make the same point more broadly — sleep loss and untreated sleep disorders spill into daily safety, work performance, and drowsy driving. (healio.com) ### So what do you actually do with this? The practical takeaway is boring but powerful — make your schedule easier for your clock to follow. Keep sleep and wake times regular. Get bright light at the right time of day, especially in the morning if your schedule has drifted later. Be careful with late-night light and stimulation. And if your sleep se(healio.com) Treatments can include lifestyle changes, bright light therapy, and melatonin timed for the specific disorder. (nhlbi.nih.gov) ### What’s the bottom line? The bigger shift in sleep medicine is simple — stop treating sleep like a nightly bucket you fill with hours. Your body cares about when those hours happen. Sharkey’s point is that if the clock is off, more effort does not always fix the problem. Better timing often does. (healio.com)
