Earthly Materials: Journeys Through Our Bodies’ Emissions, Excretions, and Disintegrations by Cutter Wood

Here’s a topic most people would rather ignore: bodily fluids. Essential to life and health, they’re also deeply stigmatized and rarely discussed. But what if we faced them head-on? What if we tried to visualize just how much material our bodies expel over a lifetime?

Take feces, for instance. Over a typical 75-year lifespan, the average person will produce approximately 3,500 kilograms—enough to overflow a 20-foot shipping container. That’s not all. Alongside that comes an estimated 38,000 liters of urine. These staggering quantities are only the beginning.

In Earthly Materials: Journeys Through Our Bodies’ Emissions, Excretions, and Disintegrations, author Cutter Wood takes a bold, unflinching look at what we shed, expel, and emit over the course of our lives. From hair and semen to menstrual blood, tears, and even the energy we release measured in joules, Wood presents the data with humor, humanity, and insight. These aren’t just gross facts—they’re the raw materials of our lives.

To live is to constantly cast off parts of ourselves. Stop urinating, stop defecating, stop exhaling—and death quickly follows. Though we often dismiss these byproducts as shameful or disgusting, they perform vital physiological roles. More than that, they tell stories. The color of our snot, the frequency of our flatulence, the rhythm of our breath—all paint an intimate portrait of who we are.

Yet our bodily emissions aren’t just personal. Across history, how we’ve handled, hidden, or revered these substances has helped shape civilizations. From ancient sanitation systems to religious taboos, from medicinal uses of urine to the politics of menstruation, our collective relationship with our body’s outputs has always been complex—and revealing.

Earthly Materials unfolds over twelve vivid chapters, each exploring one substance we excrete. Some chapters are rooted in history: What did cities do with all that waste? Others lean into philosophy: Is there ever a rational reason to cry? Still others investigate scientific frontiers: Could mucus actually be influencing evolution?

Cutter Wood’s exploration is funny, strange, and surprisingly profound—a compelling reminder that what our bodies discard may be key to understanding who we are. If you’re looking for a conversation starter, or just want to see the human body from a refreshingly honest perspective, this is the book for you.