In this episode, I sit down with Dr Kristen Knutson to explore circadian health, what it actually means, why it matters for cardiometabolic health, and how modern life quietly disrupts our internal rhythms. We unpack how light exposure, meal timing, exercise, and daily regularity influence everything from blood pressure to metabolism.
We also discuss how circadian health overlaps with sleep health but is not the same thing. Dr Knutson helps clarify common misconceptions about melatonin, wearables, waking during the night, and why many of us underestimate how much timing influences our biology.
What We Cover
- What “circadian health” means, and how it differs from (but overlaps with) sleep health
- Why internal clocks exist throughout the body, not just in the brain
- How circadian disruption can show up as jet lag or “social jet lag” without travelling
- The role of morning light, and why evening light can delay your rhythms
- Why meal timing matters independently of calories, and the simplest rule most people can follow
- What time restricted eating looks like through a circadian lens, and why adherence matters
- Exercise timing: what we know, what we do not, and the key takeaway for most people
- Why waking during the night can be normal, plus practical strategies for falling back asleep
If there is one takeaway from this conversation, it is that circadian health does not require perfection. Small improvements to timing and regularity can support better sleep, metabolic health, and long-term wellbeing.
To connect with the guest, follow Dr Kristen Knutson on LinkedIn and explore her research profile via Northwestern Feinberg.
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More about Kristen Knutson
Kristen Knutson, PhD, is an Associate Professor in the Departments of Neurology and Preventive Medicine at Northwestern University Feinberg School of Medicine, Chicago. Her research focuses on the association between sleep, circadian rhythms and health, including cardiometabolic and cognitive function. She primarily focuses on these associations out in the “real world” (outside the laboratory) by examining habitual sleep and behavioral patterns and biomarkers of health. In addition, her research examines whether sleep and circadian health vary by gender, race, ethnicity or socioeconomic status. She has examined sleep and health in a variety of populations, including large observational studies in the U.S. as well as in international locations such as Haiti and Brazil. Her overarching goal is to understand the role of sleep and circadian health in overall health and well-being, and, ultimately, to determine how to improve sleep and circadian health in diverse groups.
