Everything You Thought You Knew About Fat Is Wrong

So much of the conversation surrounding health and diet still centres on the idea that too much fat isn't good, that fat on a pork chop equals fat on the belly. Certainly, for those born or brought up in the '60s and '70s, fat will probably always be a quiet enemy to be wrestled with. In the fridges of our grandparents we'll find whole milk and good butter, but, skip a generation to our mothers and aunts and you'll find margarine, skimmed milk so weak it's almost grey, and low-fat yoghurts galore.

Something happened in the '60s that turned the previously balanced, economic approach to food and eating—three meals, plenty of high-fat dairy, cheese, eggs, meat when it could be afforded, veg, and grains—on its head. Heart disease was being discovered and treated more, and, in an effort to get to the bottom of it, a pathologist named Ancel Keys persuaded the US government that saturated fat was the primary culprit. Only, the science was, as many would discover, soft. Not entirely reliable. But it didn't stop the fat-is-bad dogma becoming completely ingrained in the minds of the western world.

Now, it seems, the war on fat is over. TIME did a cover feature on it. There's plenty meaty evidence that says it's sugar that kills, not fat. A lot—if not most of—this evidence is presented in Nina Teicholz' groundbreaking book, The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet. The product of nine years of scientific research, the book is a big, reality-giving slap around the face, telling us that everything we thought about fat was, and is, wrong.

Make mine a well-marbled rib of beef, nice and rare, cooked in half a pat of butter.

MUNCHIES: Hi Nina. What is the central thesis to The Big Fat Surprise, which, by the way, I found as un-put-down-able as Gone Girl? Nina Teicholz: Ha! Amazing. Thank you. I think the book's main contribution is to lay out the argument that saturated fats are not, contrary to what we have been lead to believe for over five decades, bad for our health, and to examine the unintended consequences of removing saturated fats from our diets.

The book is a culmination of nine—nine—years of research. Right. I didn't think it would take so long! It wasn't always a sustained effort, i.e. I wasn't working on it every single day in those nine years. I'm not an experienced book writer and had no comprehension of the magnitude of scientific literature on the subject.

In the book you talk a lot about the fat found in meat and why we shouldn't be afraid of it. Were you a meat eater before embarking on your research? Not much of a meat eater, no. Previous to the book I was mostly vegetarian and, actually, writing a restaurant column for a publication that couldn't pay. So, I was eating whatever the restaurant wanted to give me. That meant red meat, poultry, fish, foie gras...

How did you find foie gras the first time? Hmm. It was a very earthy, complex, and textured taste. Very new.

You say in the book, "Almost nothing we commonly believe today about fats generally and saturated fats in particular, appears, upon close examination, to be accurate." That's pretty terrifying. How did we end up here? Our distrust of fats is over 50 years old now. We've been told since the early '60s that fats are bad for us, and this view was launched by one, deeply flawed and controversial study—Ancel Keys' Seven Countries. In it, fat—particularly saturated fat—heart disease. Only, upon inspection, there were many methodical problems with that study, and the data did not, ultimately support that conclusion. It's quite surprising.

So you're saying that the massive, percolating effect of this study—my aunt still refuses to use real butter on toast—in the '60s was all based on bad science? It's quite unbelievable. I remember coming across Gary Taube's The Soft Science of Dietary Fat article in Science magazine back in 1999 and was profoundly shocked. My interest was launched by that article. When you realise the weak science upon which this low-fat dogma rests, it's hard to comprehend. The belief that fat makes you fat, and that it's bad for health, is so deeply ingrained.

What have some of the consequences of the ubiquitous low-fat diet been, then? Cutting fat from our diets has led to us eating more carbohydrates (25 percent more in the last 30 years in the US), part of which is more sugar, since the low-fat diet became widely adopted. It also means we're eating vegetables oils that didn't exist in the last century—soybean, safflower, corn, etc.—and that have always had the problem of being unstable when heated and potentially leading to health problems.

These are the ones that oxidise when heated? Yes, and the ones found in deep-fat fryers since trans-fats have started to be eliminated from the food supply.

The wrong oils is one thing, but I don't think I know many people who would look at the thick, hard, white fat on a beef forerib and think, that's gonna do me good. Traditionally, though, hunter-gatherers would—and still do—favour the fattiest part of the animal first. Inuit population was observed giving the tenderloins to the dogs, because that cut was considered too lean. Lean meat was not valued. By contrast, the viscera, the eyes, glands and organ meats were most favoured because they are fat more nutritious.

Well you only need to look at a piece of liver to know it's good for you. You say for a diet high in fat to be good for us, though, we need to restrict our carbohydrate intake? I can never, and will never, give up potatoes. Yes. I would not argue for an extreme diet, but, a high fat diet restricted in carbs is optimal. If you eat a diet that is both high in fat and high in carbohydrates, then there's some evidence to suggest it might lead to inflammatory effects. So, have your roast dinners, keep the fat on the beef, but just don't follow it with a huge cake afterwards.

What about exercise? You don't talk about how exercise is essential in a high fat diet? I don't think there's any indication that you need to exercise to work off a high fat diet.

OK. So what do you make of the modern protein phenomenon? It's all people seem to talk about right now, diet-wise. A high protein diet without enough fat is not a healthy diet. We need fat to survive, for our bodies to work properly. Our bodies can't actually process protein without fat or carbohydrates. However, the current preoccupation with protein may be a reflection of the fact that this is an easier way for people to reintroduce foods that have been omitted from our diets —eggs, butter, full-fat dairy. It's easier to say that you're eating these for the protein than for the fat. You'd never hear anyone saying, "Oh, I'm eating this steak because I need it for the fat," would you?

No. Have you found it hard to bring people round to the "fat is great" way of thinking? Even with all your research? Well, it did take a while for me to change my diet. I started eating things like meatballs in cream sauces, and think, How can this work? I had fought an extra ten pounds for much of my young adult life. In college, when I went to see a nutritionist, she said to cut out meat and fat. But of course this didn't work. There was no internet then to research the science that might not be mainstream, so I had no other resources.

Our grandparents' generation didn't have these problems. Right. My parents' generation grew up having Sunday roasts and drinking whole milk. Even in my own childhood, we'd get bottled whole milk delivered to our doorstep and I remember it being delicious. Since the early '60s, however, come to hold the intuitive belief that the marbled fat on a piece of meat would wind up as the fat on our belly. But it turns out that this is not true… How could we possibly imagine that bacon might be better for us than oatmeal?

How have you changed the opinions of your family, the people close to you? It takes a long time for people to reorient their ideas about fat and diet generally. In year five or so of writing the book, my husband turned to me and asked, "Are you really saying that sugar is bad?" My family members have obviously changed the way they eat, though, and many friends tell me that reading the book has made them change their diets.

Well, it's pretty much a scientific encyclopaedia—all 1,300 footnotes of it—lambasting what we once thought as true. Yes, I think it had to be a brick of a book to be persuasive… Some friends now send me text messages of them eating hamburgers, or telling me about the bacon and eggs they had for breakfast. It's great. And some people have written to me about their profound transformations on this diets—literally hundreds of pounds of weight loss or stemming the progress of diabetes. For me, it's been liberating to look at food and not fear the fat.

Reading your book did make me feel like food felt much more open with possibility. I'm so glad. It made me want to go back and look at more historical recipes. I rediscovered my grandmother's meatballs in cream sauce, but want to know more.

Me too! Thanks, Nina.