NOVA Season 2 Episode 9 What Time is Your Body?

What Time is Your Body? is the ninth episode of the second season of the documentary television series NOVA. The episode explores the concept of biological clocks, also known as circadian rhythms, and their impact on human health.

The show begins by introducing the idea that biological clocks are present in all living organisms, from bacteria to plants to animals. These internal clocks are responsible for regulating a wide variety of biological processes, including sleep, digestion, and hormone production. The episode notes that while humans are not the only animals with circadian rhythms, our modern lifestyles often require us to suppress or ignore these natural cycles.

The first third of the episode focuses on the history of circadian rhythm research. Viewers learn that the first modern study of biological clocks was conducted in the 1950s by a team of researchers studying fruit flies. Since then, researchers have made significant progress in understanding how these internal clocks work, and how they are affected by external factors like light and temperature. We see interviews with some of the scientists who have made important discoveries in this field, including Jeffrey C. Hall, Michael Rosbash, and Michael W. Young, who were awarded the Nobel Prize in Physiology or Medicine in 2017 for their work on the molecular mechanisms of circadian rhythms.

The episode then turns to the ways in which our modern lifestyles can disrupt our natural circadian rhythms. For example, it is noted that artificial light sources (such as the screens on our phones and laptops) can trick our bodies into thinking it is daytime, even when it is late at night. We also learn that shift work and jet lag can disrupt our internal clocks, leading to a range of health problems, from insomnia and depression to obesity and diabetes.

To further examine the effects of artificial light on our circadian rhythms, the show takes us to a sleep laboratory at the University of Colorado Boulder. Here, researchers are studying the impact of different types of light on the body's internal clock. The episode shows several experiments in which volunteers are exposed to various types of light (including bright white light, blue light, and dim red light) for several hours before going to bed. The researchers monitor the volunteers' sleep patterns and hormone levels to see how the different types of light affect their circadian rhythms.

The final portion of the episode looks at some of the potential applications of circadian rhythm research. For example, it is noted that some companies are experimenting with "circadian lighting" in the workplace, which adjusts the color and intensity of light throughout the day to reflect the body's natural rhythms. The hope is that this will help workers feel more alert and productive during the day, and sleep better at night. The episode also highlights some of the ways in which researchers are working to develop treatments for circadian rhythm disorders, including drugs that mimic the effects of natural hormones.

Overall, What Time is Your Body? is a fascinating exploration of an often-overlooked aspect of human health. The episode is both informative and engaging, using a mix of interviews, experiments, and animations to help viewers understand the complex world of circadian rhythms. Whether you're a biology buff or simply interested in improving your own health, this episode of NOVA is well worth watching.