Florence Williams’ book considers breasts from both a social and scientific view.

Florence Williams’ new book sets the record straight on mammaries.

A writer for the New York Times, Slate, Mother Jones and O magazine, journalist Florence Williams could’ve chosen anything for the topic of her first book. She chose boobs. Why? After becoming a mother, she became curious about exactly what was in the breast milk she was feeding her baby. “Breasts: A Natural and Unnatural History” (W.W. Norton, $25.95) examines the history, functionality and ever-changing nature of women’s breasts.

What was your favorite discovery about breasts?
That [human] breasts are so unique in the animal kingdom. All mammals have mammary glands, but ours stick around, permanently encased in their cute, fatty packages, regardless of our reproductive or lactational status.

You write that breast milk contains compounds similar to cannabis.
The cannabinoids in milk — like many substances not replicated in formula — are probably there for a reason. Perhaps they help the baby regulate her appetite, first through stimulating “the munchies” and then by making the baby relaxed so it doesn’t overeat.

There’s even an underground economy around breast milk.
As we learn more about the miraculous, immune-boosting components of breast milk, there is more of a demand for it, both for premature infants and even for immune-compromised adults. The substance is unregulated, sort of like home-brewed [beer] or raw-milk foods, so a black market has emerged.

Did any of your research relate to breast cancer?
Our breasts are forced into a life they didn’t expect — fattier diets, modern reproductive choices, pharmaceuticals like hormone replacement therapy, industrial chemicals. In other words, modern life is causing more breast cancer.

Did your feelings about your own breasts change while writing this book?
I now know what evolutionary miracles they are. We have shortchanged them by only looking at them through a sexual lens. Breasts deserve attention beyond just for how great they look.

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