Photo of bookshelf in Bryn Nelson's office showing some of the reference books for his book, Flush.

Bryn Nelson—Flush: The Remarkable Science of an Unlikely Treasure




Bryn Nelson
Grand Central Publishing, September 13, 2022, $30.00
ISBN-13: 9781538720028
Hachette Audio (read by Fred Berman) ISBN-13: 9781549160820
E-book ISBN-13: 9781538720035

Nelson reports:

The initial kernels for Flush appeared in 2014, when I wrote a feature exploring the rise of fecal microbiota transplants for the British magazine Mosaic. I was fascinated by how the relatively crude practice of transplanting the microbiome of a healthy individual into someone sickened by a Clostridioides difficile bacterial infection led to a cure far more often than a course of potent antibiotics did. Even so, patients were dying needlessly due to disgust, ridicule, and the refusal of some doctors to consider the technique.

I began thinking about how we assign value to the things around us, and how something that we have assigned the least amount of value—our poop—is actually one of the most powerful and versatile natural resources. Although it took a while for me to fully commit to a book project, I gathered material along the way, including during some vacations to Norway, Cuba, and locations around the U.S.

Bryn Nelson

Bryn Nelson

I developed my book proposal in 2019 with the help of an accountability buddy and a few sample proposals. I then created a detailed spreadsheet based on information from Publishers Marketplace to identify which agents to pitch. After I found my agent, Anna Sproul-Latimer, she and I worked for about eight months to refine the proposal before pitching it to multiple publishing imprints. Two bid on the book, and I decided to go with Grand Central Publishing. My wonderful editor, Maddie Caldwell, helped me further shape the book over the next 18 months.

Covid-19 sharply limited my long-distance travel, so I focused on making the most of closer opportunities. Aspiring authors should know that publishers routinely split an advance into four parts, meaning that I only had one-fourth available for research and travel. I also assumed the full fact-checking costs, which ate up most of the advance’s second part. I would recommend starting the process as early as possible so you don’t run out of time. My book’s highly involved fact-checking took three months but I believe Flush is far better because of it.

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Tell your fellow NASW members how you came up with the idea for your book, developed a proposal, found an agent and publisher, funded and conducted research, and put the book together. Include what you wish you had known before you began working on your book, or had done differently.


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November 1, 2022

Advance Copy

The path from idea to book may take myriad routes. The Advance Copy column, started in 2000 by NASW volunteer book editor Lynne Lamberg, features NASW authors telling the stories behind their books. Authors are asked to report how they got their idea, honed it into a proposal, found an agent and a publisher, funded and conducted their research, and organized their writing process. They also are asked to share what they wish they’d known when they started or would do differently next time, and what advice they can offer aspiring authors. Lamberg edits the authors’ answers to produce the Advance Copy reports.

NASW members: Will your book be published soon? Visit for information on submitting your report.

Publication of NASW author reports in Advance Copy does not constitute NASW's endorsement of any publication or the ideas, values, or material contained within or espoused by authors or their books. We hope this column stimulates productive discussions on important topics now and in the future as both science and societies progress. We welcome your discussion in the comments section below.

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