Dr. Cate Shanahan on Dark Calories and Seed Oils

Deep Nutrition author Dr. Cate Shanahan explains why she wrote Dark Calories and how she thinks about seed oils, oxidative stress and root causes.

By Harry Gray · Nov 4, 2026 · 3 min read

By The Meat Mafia (Harry Gray and Brett Ender)

Dr. Cate Shanahan's first book, Deep Nutrition, came out in 2009. It ended up on our office shelf twice.

That first edition had an appendix with a big idea: that nutrient deficiency and toxicity sit at the root of many diseases.

She wanted to build on it in the newer edition. Her agent, she says, told her to save it for another book.

So she did. That other book became Dark Calories.

"I've been obsessed about this book for four years" (01:00)

Her frustration is with how medicine talks about root causes. She says what usually gets called a root cause, like not exercising enough, is really a risk factor.

She wanted to go deeper, into oxidative stress and what she sees as one of its biggest drivers in the modern diet: industrial seed oils, or what she calls the "hateful eight."

She admits the message is hard to land. Some doctors brush it off. Others read the book and ask her to speak to their medical group.

"really dark calories is my attempt to fix modern medicine." (06:00)

Below is her case, in her words, with timestamps so you can hear it yourself. These are her views, not medical advice. Talk with your own clinician before you change your diet or medications.

Listen to the full episode · Watch on YouTube

TL;DR: Dr. Cate Shanahan says she spent years wanting to write about the root causes of disease, which she frames as nutrient deficiency and toxicity. In Dark Calories she argues that industrial seed oils deserve far more attention from medicine. Her views, not medical advice.

Who is Dr. Cate Shanahan? A physician and the author of Deep Nutrition and Dark Calories.

Key takeaways

She says Dark Calories grew out of an appendix on root causes that was cut from Deep Nutrition (04:00).
She separates risk factors from root causes (02:00).
She points to oxidative stress as the thread she wants medicine to look at (05:00).
She says the oils we eat can change what's stored in our body fat (20:00).
She cautions against very rapid weight loss without attention to diet quality (24:00).

Risk factors vs. root causes

Dr. Shanahan says medicine often names risk factors, like low exercise or genetics, as the root cause of disease. She'd rather ask why nutrient deficiency and toxicity show up behind so many conditions (02:00, 03:00).

Why body fat matters in her argument

She describes data showing more polyunsaturated fat stored in people's body fat than decades ago, and argues that this changes how well that fat works as fuel (21:00 to 23:00). She also notes that stored fat turns over slowly, over years rather than weeks (20:00).

Talking to industry experts

She says she interviewed people in the oil industry and toxicology while researching the book. Each held a piece of the picture, and she wrote chapter two to put the pieces together (25:00 to 29:00).

FAQ

Who is Dr. Cate Shanahan? A physician and the author of Deep Nutrition and Dark Calories.

What is Dark Calories about? Her case that industrial seed oils and oxidative stress deserve more attention as root causes of chronic disease.

What are the hateful eight? Her name for the common industrial seed oils she recommends avoiding.

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Not medical advice. This post summarizes a podcast conversation for education. The views are the guest's own. Talk to a qualified clinician before you change your diet, supplements or any medication.