Twice a year, many of us adjust our clocks — an hour forward in spring, an hour back in autumn when clocks line up with the sun again — a practice that dates back to the early 20th century in the UK. The idea was simple: make better use of daylight, boost productivity, and align human activity with industrial needs. Adjusting our clocks might be a gesture toward efficiency — but not necessarily toward balance.
While our clocks may shift in an instant, our biology does not. Our bodies remain tuned to a rhythm far older than the mechanical clock — the rhythm of light and darkness, sunrise and sunset, rest and activity.
In Traditional Chinese Medicine (TCM), this principle is foundational. Health is understood as living in harmony with the Qi of nature — the vital energy that flows with the seasons, the elements, and the movement of the sun. The ancients taught that we should rise with the light, rest with the dark, eat and act in alignment with the natural cycles and seasons. To fight against nature’s timing was to invite imbalance.
Centuries later, modern science is rediscovering this truth. Through the lens of chronobiology or the study of biologic rhythms, we now understand that every cell in the human body operates according to an internal 24-hour rhythm known as the circadian rhythm. This rhythm regulates our hormones, metabolism, immune system — and yes, even our fertility.
And the key regulator of this rhythm is light.
Today, surrounded by artificial light and glowing screens, we’ve unintentionally dimmed the natural cues that keep our hormonal system in tune. Understanding how light interacts with our biology — and learning to live once again in rhythm with it — may be one of the simplest and most profound ways to support fertility and hormonal health…

