For years Dr. Mark Hyman was a vegetarian who kept his intake of dietary fat to a minimum. Whole-wheat bread, grains, beans, pasta and fruits and vegetables made up the bulk of his diet, just as the federal government’s dietary guidelines had long recommended.
But as he got older, Dr. Hyman noticed something that bothered him: Despite plenty of exercise and a seemingly healthy diet, he was gaining weight and getting flabby. At first he wrote it off as a normal part of aging. But then he made a shift in his diet, deciding to eat more fat, not less – and the changes he saw surprised him.
He lost weight, his love handles disappeared, and he had more energy. He encouraged his patients to consume more fat as well, and many of them lost weight and improved their cholesterol. Some even reversed their Type 2 diabetes.
Today, as the director of the Cleveland Clinic’s Center for Functional Medicine, Dr. Hyman has become an outspoken advocate about the health benefits of eating fat. He promotes it on talk shows, educates other doctors, and has even managed to wean his close friend Bill Clinton off of his previously prescribed low-fat vegan diet.
Now in a new book called “Eat Fat, Get Thin,” Dr. Hyman takes a deep dive into the science behind dietary fat, making sense of decades of confusing health recommendations and building a case for why even saturated fats, which have long been vilified, belong in a healthy diet. Dr. Hyman argues that Americans have been misled about the benefits of fat because of a disconnect between nutrition science and food policy. In the book he challenges the nutrition orthodoxy while also exploring the food industry’s outsize influence on official health recommendations.
Recently, we sat down with Dr. Hyman to discuss his thoughts on the gap between nutrition science and health recommendations, the reason you should always plan your meals, and why he never leaves home without a stash of “emergency foods” in his backpack. Here are edited excerpts from our conversation:
Q. Why did you write “Eat Fat, Get Thin”?
A. I wrote it because we’ve been suffering from 40 years of bad advice about fat that’s led to the biggest obesity and diabetes epidemic in history. The myth that fat makes you fat and causes heart disease has led to a total breakdown in our nutritional framework. I felt it was important to tell the story of how fat makes you thin and how it prevents heart disease and can reverse diabetes. I think people are still very confused about fat.
Q. In the book you argue that nutrition recommendations are often contradictory. How so?
A. This year, for example, the U.S. Dietary Guidelines for the first time removed their longstanding restrictions on dietary fat. But they still have recommendations to eat low-fat foods. They say total fat is not an issue, but you should drink low-fat milk and eat low-fat dairy and other low-fat foods. It’s a schizophrenic recommendation from the government, and it’s the same with other professional organizations such as the American College of Cardiology and the American Heart Association. There’s a mismatch between the science and the government and professional recommendations.
Q. What’s driving this disconnect?
A. I think the government based its recommendations on some very flawed science, which took hold. It became policy that was turned into the dietary guidelines and the food pyramid that told us to eat six to 11 servings of bread, rice, cereal and pasta a day and to eat fats and oils sparingly. It’s very hard to overturn dogma like that. It’s embedded in our culture now. It’s embedded in food products. The food industry jumped on the low-fat bandwagon, and the professional associations kept driving the message. Unfortunately the science takes decades to catch up into policy and into practice. And I’m trying to close that gap by bringing awareness to the latest science on how fats and carbs work in your body.
Q. You reviewed hundreds of studies while writing this book. What is your conclusion on saturated fat?
A. It’s a huge area of controversy. But large reviews of randomized trials, observational research and blood-level data have all found no link between saturated fat or total fat and heart disease. Yet there are still recommendations to limit saturated fat because it raises total cholesterol and LDL cholesterol. But it also raises HDL, and it increases cholesterol particle size, so you actually get a net benefit.
Q. What do you say to scientists who argue that saturated fat does in fact cause heart disease?
A. I think the challenge with the research is that a lot of the data combines saturated fat in the context of a high-carbohydrate diet. The real danger is sweet fat. If you eat fat with sweets – so sugar and fat, or refined carbohydrates and fat – then insulin will rise and it’ll make you fat. But if you eliminate the refined carbs and sugar, that doesn’t happen. I think saturated fats can be bad in the context of a high-carbohydrate diet. But in the absence of that, they’re not.
Q. What foods do you eat and recommend to your patients?
A. What I eat is a cross between paleo and vegan diets. It combines elements of the two, so I call it a “pegan” diet. It’s low in sugars and refined carbs, and it’s very high in plant foods. About 70 to 80 percent of your diet should be plant foods. It should also include good-quality fats like nuts and seeds, olive oil, avocado, coconut oil and fatty fish. It should basically include whole, fresh food that’s unprocessed and high in fiber and phytonutrients. I always say that vegetables should make up 50 to 75 percent of your plate.
Q. In a world where fast food is everywhere, wouldn’t that be fairly difficult for most people?
A. It’s actually very easy to eat well if you just know what to do. The reason most people don’t succeed is they don’t plan their food. They plan their vacations, they plan their kitchen redesign, but they don’t plan out what they’re eating, and that’s a recipe for failure. I always think through how and where I’m going to get my food every day of every week. I also carry with me a set of emergency food so that I’m never in a food emergency.
Q. What are the “emergency foods” that you carry?
A. I have to protect myself from myself because I’ll eat whatever if I’m hungry in an airport. So I always carry packets of almond butter, cashew butter, an Evolution bar, a Bulletproof bar, a Tanka bar and a KIND bar. I basically have fat and protein as my snacks, and I have enough food in my bag to last an entire day so I don’t make bad choices.
Q. We talked a lot about fat. But what is one overarching message you would most like people to understand?
A. I think we have to get rid of the prevailing dogma that all calories are the same, and that we just need to exercise more and eat less, which is what the food industry and the government promote. The truth is that you can’t exercise your way out of a bad diet. Metabolism is not a math problem. It’s a hormonal problem. Food is not just energy. It’s information. It’s instructions that turn on or off different switches in your body that regulate hunger and metabolism. Obesity is not about how much you eat. It’s about what you eat. If you just focus on quality, not calories, then the quantity takes care of itself.