Shanahan, Catherine. Dark Calories: How Vegetable Oils Destroy Our Health and How We Can Get It Back. Hachette Go, 2024.

Most people have no idea what they’re eating. They’ll spend money on “organic” snacks, cut back on red meat because someone on TV told them it’s bad, and then drown everything in vegetable oil because the government once decided it was “heart-healthy.”

Meanwhile, I take one look around my school and see boys already developing the puffed-out, sagging faces of middle-aged men. Some of them have skin like they’ve been deep-fried. Others can’t get through the afternoon without looking like they need a nap. And they don’t know why. They just assume this is how things are. Their parents are fat, their teachers are fat, the people giving them dietary advice are fat, and it’s all “normal.”

Well, it isn’t. And Dark Calories by Dr. Catherine Shanahan explains why. The book is basically a demolition of the modern diet, specifically the junk we’ve been told to cook with—vegetable oils. If you want to understand why so many people are tired, overweight, and falling apart before they even hit middle age, this book spells it out in detail.

Dr. Shanahan isn’t some random diet guru. She’s a biochemist who spent years treating patients and wondering why even young, “healthy” people were showing signs of metabolic damage. The answer, she found, was in the oils.

Vegetable oils—canola, soy, sunflower, corn, cottonseed, safflower, grapeseed, and rice bran—are the foundation of almost every processed food. They’re used for frying, baking, and dressing salads. Restaurants use them because they’re cheap. Supermarkets fill their shelves with them. Even so-called “health” foods are packed with them. And they are, as Shanahan puts it, slow poison.

Why? Because these oils oxidize easily, creating toxic compounds that damage your cells. They get into your fat stores and make your body run less efficiently. They inflame your gut, mess up your metabolism, and even scramble the way your brain processes hunger signals. In short, they make you weak, slow, and ugly.

Shanahan makes a simple: eating a large portion of fries cooked in vegetable oil delivers the same oxidative stress as smoking 24 cigarettes. That’s not some dramatic exaggeration—it’s backed by research. The amount of cell damage caused by these oils is staggering, and yet they’ve been marketed as healthy alternatives to traditional fats like butter, lard, and coconut oil.

It’s no wonder people are getting fatter despite “eating healthy.” They’ve been tricked into swapping real food for chemically processed industrial sludge. Worse still, these oils stay in your body—sometimes for months—changing the way your fat cells function. That means even if you clean up your diet today, you’re still running on bad fuel for a while.

One of the best parts of this book is the way it dismantles the entire scam that got us here. Shanahan traces how the food industry and certain “experts” hijacked public health policy. They convinced people that natural fats—things humans have been eating forever—were dangerous. Butter and beef fat were demonized, while margarine and seed oils were pushed as modern, scientific improvements. The result? Heart disease, obesity, diabetes, and metabolic disorders skyrocketed.

Of course, the government hasn’t admitted any of this. It just keeps adjusting its food recommendations while pretending it wasn’t responsible for decades of dietary misinformation.

Unlike a lot of health books that just tell you what’s wrong, Dark Calories actually gives you a plan to fix things. And it’s pretty simple:

• Stop eating vegetable oils. This means avoiding most processed foods, fast food, and restaurant meals unless you know they’re cooked in real fats.
• Use real fats—like butter, ghee, tallow, coconut oil, and olive oil.
• Eat nutrient-dense foods that support your metabolism.
• Get rid of the idea that fat is bad and carbs are good. It’s not that simple.

This isn’t about going on some miserable, restrictive diet. It’s about stopping the slow poisoning of your body and replacing trash with real food.

I don’t eat like an idiot. I exercise, I eat properly, and I make sure I stay in peak condition. But I see what happens to people who don’t. And the problem isn’t just laziness—it’s ignorance. If you’re following “official” dietary advice, you’re basically being told to wreck your metabolism. You’re being sold a lie that keeps food companies rich and keeps you hooked on cheap, addictive garbage.

Most of my classmates don’t care about any of this. Not yet. They assume they’ll be fine. But I see the signs already—soft, bloated faces, tired eyes, an inability to focus. They’re young now, so they think it doesn’t matter. But fast forward ten years, and they’ll be 26 looking 40, wondering where it all went wrong.

I’m not letting that happen to me. And if you have any sense, you won’t let it happen to you either.

Dark Calories is one of those books that makes you angry—not because it’s wrong, but because it’s so obviously right. We’ve been lied to for decades, and the results are everywhere. This book lays out the truth in simple terms: vegetable oils are destroying people’s health, and the only way to fix it is to cut them out completely.

If you care about your body, your energy levels, and not turning into another doughy, exhausted casualty of modern food culture, read this book. Then start actually paying attention to what’s in your food.