A conversation with investigative journalist, Nina Teicholz, author of THE BIG FAT SURPRISE: Why Butter, Meat & Cheese Belong in a Healthy Diet.
I love this book for many reasons, the most important being, that in it, Nina reveals the unthinkable: that everything we thought we knew about dietary fats is wrong. Combining scientific rigor with riveting storytelling, she argues that more, not less fat—including the saturated fats in meat, dairy and eggs—is what leads to better health and weight loss.
Dr L: How did you come to write this book?
Nina: I was a faithful follower of the low-fat, near-vegetarian diet, but when I started writing a restaurant review column, I found myself eating things that had hardly ever before passed my lips: rich meals of pâté, beef, cream sauces and foie gras. To my surprise, I lost the 10 pounds that I hadn’t been able to shake for years, and to boot, my cholesterol levels improved. To understand how this could be possible, I embarked upon what became a decade of research, reexamining nearly every single nutrition study and interviewing most of our top nutrition experts. What I was shocked to find were egregious flaws in the science that has served as the foundation of our national nutrition policy, which for more than 50 years has all but forbidden these delicious and healthy foods.
Dr L: You write, “Almost nothing we commonly believe today about fats generally and saturated fats in particular, appears, upon close examination, to be accurate.” How did we get here?
Nina: Our distrust of saturated fat dates more than 50 years, and can be traced to just one man: a bullying, charismatic but revered pathologist named Ancel Keys, whose quest for fame caused him to run roughshod over basic scientific standards. His deeply flawed “Seven Countries” study was the “Big Bang” of all our nutrition recommendations today. In an effort to quickly address the terrifying heart-disease epidemic, Keys persuaded the American Heart Association and ultimately the U.S. government to subscribe to the notion that saturated fat was our chief dietary culprit. Fat generally — and saturated fat specifically — came to be blamed for causing heart disease, obesity and cancer. Eventually this unfounded belief became ingrained as our national dogma, and many of our most esteemed nutrition scientists today endorse this idea based on the same kind of soft science that originated with Keys.
Dr L: What are the unintended consequences of the low-fat diet that resulted from this flawed thinking?
Nina: Avoiding fats has led to eating more carbohydrates—25% more since adopting the low-fat diet—and this shift (not only to more sugar but also more whole grains and fruit) has led to today’s diabetes and obesity epidemics. Cutting back on saturated fat has also meant that we are now eating far more vegetable oils, like soybean, canola and corn. These oils didn’t even exist in 1900 and now are 7-8% of all calories we eat. They have always been associated with health problems, including cancer. When heated, they oxidize and cause inflammation and gastric damage. These oils are now being used much more commonly in restaurant fryers, ever since the big fast-food chains like McDonalds and Wendy’s announced their shift to trans-fat free oils.
Dr L: A bigger story: How did bad science become the foundation our national dietary policy?
Nina: This larger story is at the heart of the book. It begins in the 1950s, when the desperate need to solve the heart-disease epidemic caused experts to jump the gun, launching dietary guidelines based on weak, incomplete science. As research dollars and institutions became invested in the idea, it became harder to reverse course, until, ultimately, the U.S. government’s adoption of the diet enshrined it in our federal bureaucracy. Biased science became a necessity. A once-loud group of critics was silenced (one, in particular, has come to be considered the “Cassandra” of nutrition). Big Food has played a role too (though less than is commonly thought) by buying off our most esteemed authorities and the science itself.
Dr L: Many readers might be surprised to learn that the low-fat diet is especially harmful to women, which is scary because women tend to diet more. Tell us why.
Nina: Women have been especially hard hit by the low-fat diet recommendations, which they have followed more religiously than anyone else over the past few decades. It turns out that women’s “good” cholesterol (HDL) drops dramatically on this diet (it does for men, too, but less so), thereby increasing their risk of heart disease. Even in the 1980s, it was found that middle-aged women with high cholesterol lived longer than those with low cholesterol, but researchers ignored this result, because they were focused on middle-aged men. In fact, all of our diet and cholesterol recommendations for decades have been based exclusively on data from men.
Dr L: Who else is at special risk?
Nina: Children are another population who were never tested before the U.S. government recommended putting them on the low-fat diet. Plenty of pediatricians objected that this diet, designed for middle-aged men, was inappropriate for growing children, but their voices were ignored. Only a few small trials were ever conducted on children and low-fat regimens, and these studies show that the diet increases the risk of nutritional deficiencies. Children grow better on higher fat diets. Our current school lunch and WIC-program policies of feeding them skim milk rather than whole are therefore alarmingly bad for their health.
Dr L: It seems the prevailing thinking on fat is that some fats, like olive oil, are the best for our health. You discovered in your research that the Mediterranean Diet is not what it’s cracked up to be. How did it come to pass that we all worship at the altar of olive oil?
Nina: The Mediterranean Diet originated from a survey of the eating habits of long-living Cretan peasants in the 1950s, who seemed to eat very little meat or dairy. However, they were surveyed shortly after WWII, when their economy was in ruins. Also, their diet was sampled during Lent, when animal foods were severely restricted. The data was therefore not any good and never grew any better. In fact, the reason that the Mediterranean Diet became celebrated and famous is that researchers fell in love with the sun-kissed, enchanting Mediterranean—and most of their studies and travel were funded by the olive-oil industry. It’s amazing how researchers, including some of the most respected people in the field today, thrived on the Mediterranean Diet conference junket. The actual science is far from impressive: it can only show that this diet is superior to the failed, low-fat diet (and what diet isn’t?). Tested against a higher fat diet, the Mediterranean regime looks far less impressive for weight loss or heart disease. Also, no one’s ever been able to pinpoint any special, disease-fighting powers of olive oil—which turns out not to be an ancient foodstuff after all but a relatively recent introduction to the Mediterranean diet.
Dr L: What about tropical oils? Are they OK?
Nina: Coconut and palm oil were condemned in the 1980s for being high in saturated fats. Yet the main campaign against them was really a trade war, organized by the American Soybean Association (ASA), to drive out the foreign competition. For years, there was a feud between the Malaysians, who are the world’s largest producers of palm oil, and the ASA. The ASA appeared to be winning, but when the Malaysians threatened to expose the trans-fat problem in hydrogenated soybean oils, the ASA decided to call a truce–and stopped its slander campaign against the tropical oil producers. These oils are good for health and are now enjoying a comeback.
Dr L: What about cholesterol? Doesn’t saturated fat raise people’s cholesterol levels and contribute to heart disease?
Nina: The evidence against saturated fat amounted to: 1. Very poorly controlled trials from the 1970s (whose flaws have since been revealed) and 2. The fact that saturated fats raise total cholesterol. In the late 1980s, it was discovered that total cholesterol is not, actually, a reliable predictor of heart disease, so the conversation shifted to LDL-cholesterol, which saturated fat also raises. However, over the past decade, many studies have shown that LDL-C has also failed to be a reliable predictor of risk. The new science shows that certain subfractions of LDL are more accurate—and saturated fat has a good effect on these. Plus, saturated fat is the only kind of food that is known to increase HDL, the “good” kind of cholesterol. In short, saturated fat was condemned when the science was still primitive. The science has evolved, but experts are stuck in old paradigms due to longtime biases and support from the statin industry.
Dr L: Robert Atkins vs. Dean Ornish (or fast forward to Gary Taubes vs. Mark Bittman) — What’s the truth?
Nina: Robert Atkins, who was an early proponent of a high-fat diet, and Dean Ornish, who espoused a plant-based diet, were the two most famous diet doctors of their day. Speaking out against the low-fat dogma that had already infiltrated the popular imagination, Atkins was seen as a quack. He was curmudgeonly and ornery—the worst possible advocate for the low-carb diet. Compared to him, Ornish came across as a scientific man of reason. But it turns out that the studies Ornish conducted were too small to be meaningful. And in fact, most of the scientific literature shows that very low-fat diets, vegan and near-vegetarian diets, such as the kind Ornish recommends, lead to obesity and greater heart-attack risk. Meanwhile, Atkins has been vindicated. When he was alive, there were few scientific studies to back up his ideas, but the last decade has seen an explosion of rigorous clinical trials on the high-fat, low-carb diet. These trials have been ignored by the low-fat obsessed mainstream, but they show, definitively, that a high-fat diet is the best for health.
Dr L: So what are the implications of your findings? How should we eat differently and how should national policy change?
Nina: The most rigorous diet trials clearly show that a high-fat, low-carb diet is better for fighting obesity, diabetes and heart disease. The question is: what kind of fat should you eat?
If you want to get your fat from red meat, eggs, whole-fat dairy or coconut butter, there’s no data to show that’s not perfectly safe—and very likely healthier than vegetable oils. Our government should change its dietary recommendations to reflect the scientific evidence. Two immediate action items: It should let whole milk back into the WIC and school lunch programs. And it should not ban trans fats without first weighing the problems of toxic oxidation products from vegetable oils in restaurant fryers.