Three decades of circadian research — on light, food, sleep and movement — carried out of the laboratory and into the way people actually live.
Together those molecular clocks anticipate the day — moving hormones, temperature, digestion, repair and alertness through a roughly 24-hour cycle.
They are set by four signals we control. Click through the day to see what each one governs.
See the research →Each is a research programme, a chapter, and a decision you make today.
How specialised sensors in the eye tell the brain what time it is — and why the indoor day confuses them.
Time-restricted eating: what the length and placement of the daily eating window appears to do.
Why the hours you keep matter as much as the hours you log, and what the night shift repairs.
How movement interacts with the clock in muscle, and where the evidence on timing stands.
“I grew up between two rhythms: one household ran on the railway's night shifts, the other rose and rested with the sun. The difference was visible in their health long before I had the vocabulary for it.”
That childhood observation became a question, the question became a laboratory, and the laboratory became a body of work on how the timing of light, food, sleep and movement shapes human health.
Read the full biography →The book that brought circadian science to a general readership: what the internal clock governs, and how aligning the day with it may influence energy, sleep and long-term health.
Explore the bookA science-based examination of eating windows, circadian rhythm and metabolic health — revised in 2025 to reflect newer clinical evidence.
Explore the bookA full conversation on eating windows, light, sleep and the clinical evidence behind time-restricted eating.
Watch on YouTube →Reading the last five years of trials without overstating them.
Too little light by day, too much by night — the modern inversion.
What we owe the twenty percent who work against the clock.
Keynotes and lectures for conferences, universities, medical and scientific meetings, and corporate audiences — always grounded in published research.
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