By
Elliot Resnick
Eating is not a simple endeavor in our health-conscious society. A juicy steak may taste good, but conventional wisdom has it that red meat should best be eaten sparingly. And that delicious schmaltz that so many Jews ate at youngsters is now regarded almost universally as a sure killer.
According to science journalist Nina Teicholz, though, this conventional wisdom is flat out wrong. Teicholz spent nine years researching the origins of – and scientific basis for – the “fat-is-bad” premise and published her findings in 2014 in what became a New York Times bestseller, The Big Fat Surprise: Why Butter, Meat & Cheese Belong in a Healthy Diet (Simon & Schuster). Today, she serves as executive director of The Nutrition Coalition, promoting evidence-based nutrition policy.
The Jewish Press: For decades, experts have told us that fat is bad for you. You say it isn’t. Why should someone trust you over them?
Teicholz: The thesis of my book is that saturated fat isn’t bad for you. The idea that fat isn’t bad for health is actually accepted today by our highest nutritional authorities – although nobody really knows that because it hasn’t been publicized due to the incredible amount of politics in the field of nutrition. But if you go to the federal government’s website on the “Dietary Guidelines,” you cannot find any publication since 1995 with the words “low fat” in them.
Why should people trust you that saturated fat isn’t bad when the experts say it is?
First, I would say to read the book. Second, experts have been wrong before, especially in the field of nutrition. Three generations of experts were wrong about dietary cholesterol. In the last five years, both the American Heart Association and the U.S. government have dropped their caps on dietary cholesterol, which is the reason people were avoiding egg yolks and liver, for example. So one of the pillars of our dietary advice for 50 years turned out to be a mistake.
All experts for generations have also recommended a low-fat diet, but the American Heart Association and U.S. government have both dropped that low-fat recommendation as well. So in both those cases, a universe of experts have been wrong and have had to retract themselves.
The official scientific consensus now is that cholesterol is not bad for you?
Yes, it’s an incredible story. Ever since 1961 when the very first nutrition guidelines were issued by the American Heart Association, Americans have been told to avoid dietary cholesterol as a measure of protection against heart disease. But in 2013, the American Heart Association dropped that recommendation with a single line in a scientific paper stating that there is insufficient evidence to support that recommendation.
And then the U.S. Dietary Guidelines, which tends to follow the American Heart Association, said in a sentence or two in 2015 that it finds insufficient evidence for the recommendation to restrict one’s dietary cholesterol.
So experts can be wrong, and in many cases it requires outsiders to confront longstanding paradigms. I don’t rely on NIH grants. I don’t need to be invited to top conferences. I don’t need to talk to nutrition scientists at the water cooler. I don’t depend upon research grants and all those things that scientists depend on for their careers. So I have more liberty.
Most people think of science as a noble, dispassionate endeavor with researchers carefully following the facts wherever they lead. You write, though, that sometimes a few powerful personalities at the heads of key institutions or scientific journals use their positions to advance their own pet theories and suppress competing ones, creating a scientific “consensus” by default that has nothing to do with hard evidence. Can you elaborate?
In writing this book, I started off with the same idea you expressed – that science is this sober, respectful practice of responding to observations, and if your hypothesis doesn’t explain your observations, you change your hypothesis. But what I found instead was that politics explains so much more of what goes on in nutrition than rigorous science.
The hypothesis that saturated fat and dietary cholesterol is bad for health took hold at the very highest levels in the 1950s and ‘60s, and soon after it became virtually impossible to challenge it. When respected professors did studies whose results contradicted this hypothesis, their research findings were simply ignored or, in some cases, went unpublished.
One researcher at Rockefeller University, Pete Ahrens – who was one of the most respected fat experts in the country – told me he stopped getting invited to expert conferences and had trouble getting his papers published or his research funded because he challenged the low-fat hypothesis. That is a common story I head from many researchers.
You write interestingly that many nations consume much more meat than Americans, yet don’t suffer from heart disease nearly as much as Americans do. Which nations are these?
The Germans, Swiss, and French all eat much more saturated fat than we think is healthy but have low rates of heart disease. The Masai warriors in Kenya eat pounds of red meat a day, along with the blood and milk. They don’t eat any fresh fruits or vegetables or grains. And yet, scientists who studied them in the 1970s – and took 400 electrocardiographs – could find no evidence of heart attacks among these people. The Masai were also found to have very low blood cholesterol and low blood pressure, which, remarkably, did not rise with age.
I present these examples, not to say we should eat like the Masai warriors – although there’s no evidence you couldn’t – but to show that they contradict the hypothesis that saturated fat and cholesterol are bad for your heart. [Studies on these and other nations] were published in peer-reviewed journals decades ago; experts have known about them, but they’ve simply ignored them.
Some people may argue that even if we can’t prove that saturated fat or cholesterol is bad for you, why take a chance? Might as well play it safe and avoid these foods just in case they do cause heart disease. What’s your response?
Red meat is a very low-calorie way to obtain a complete protein. It contains Vitamin A, all of the B vitamins, choline, and minerals such as iron, copper, zinc, selenum and manganese. Quite a few of these are not available in plant foods, especially Vitamin B12. Deficiencies in B12 are really dangerous for women, especially of child-bearing age if they want to have healthy normal children. The symptoms of deficiencies in B12, for example, are almost exactly parallel to the symptoms of autism.
So there is potential harm in eliminating a food that delivers so many essential nutrients. Liver in particular is the most nutrient-dense food on the planet, but many people no longer eat it even though they might remember having chopped liver with their grandparents.
Also, it’s important to note that any time you eliminate one food, you have to replace it with something else. So if you eliminate steaks for dinner, what do you to replace that with? Do you replace it with pasta or vegetables? Well that’s a high-carbohydrate meal. So all of a sudden you go from a zero-carbohydrate meal to a high-carbohydrate meal with only a fraction of the vitamins and other nutrients you need for good health.
Carbohydrates and, to a certain extent, polyunsaturated fats (found in vegetable oils) are the “enemy” in your book. You write, interestingly, that heart disease was actually quite rare until the modern era when people started eating carbohydrates in large amounts. Can you elaborate?
We’ve been living with obesity, diabetes, heart disease, Alzheimer’s, and cancer for so long that we assume they’ve always been present. But that’s not the case. Heart disease, for example, was exceedingly rare right through the early 1900s.
Obesity, diabetes, gout, Alzheimer’s etc. are all relatively recent epidemics, and historically they’ve all appeared in populations more or less simultaneously when refined carbohydrates – particularly sugar – were introduced into these populations’ diets.
People who have studied relatively isolated indigenous populations have noticed that the health of these populations plummeted, almost overnight, with the introduction of sugars and other refined carbohydrates [i.e., modern Western foods] into their diets. Many of these peoples previously hunted animals and lived in good health, so clearly saturated fat wasn’t the problem.
You claim fatty foods are not bad for you, but the fact is that we now live longer than our grandparents who ate all these foods. Doesn’t that contradict your thesis?
We do live longer, but to what should we attribute that to? Is it our diet? Other explanations are that we have conquered all the infectious diseases that used to kill people.
Since 1980, Americans have suffered from rising rates of obesity, type 2 diabetes, heart disease, etc. Although heart disease is treated more effectively now with earlier diagnosis and medications, the incidence itself has actually not declined. We’re also seeing rising rates of cancer and Alzheimer’s. We now even have infants with obesity and diabetes. That was rare or non-existent until quite recently.
At the end of your book, you write that “a beet salad with a fruit smoothie for lunch is ultimately less healthy for your waistline and your heart than a plate of eggs fried in butter. Steak salad is preferable to a plate of hummus and crackers. And a snack of full-fat cheese is better than fruit.” Are you exaggerating?
No. In recent years, there have been numerous position statements signed by nutrition experts worldwide saying that saturated fats are better for your cardiovascular health than carbohydrates. If you compare the two – and this has been done – saturated fats are definitely better.
My father was a physician and researcher and his stock answer to many dietary questions was, “Different people are different.” Is it possible that we should be advocating different diets for different people and that the modern tendency to make sweeping recommendations for all 320 million Americans is misguided?
Yes, I think that’s an excellent point. It should be said that that the low-fat diet was developed to fight disease in middle-aged men and never took into consideration the different nutritional needs of women and children, especially growing children. So I’m hugely in favor of abandoning our one-size-fits-all recommendations and diversifying the number of officially-permitted diets so that doctors can recommend them.
People don’t realize that doctors are often very constrained in what they can recommend. They have to follow the official advice; otherwise, in some cases, they risk medical liability.
You used to be a vegetarian, correct?
Yes, I was a low-fat vegetarian for over 25 years, and I was always struggling with my weight. I exercised fanatically, always trying to be thin, but it wasn’t until I did the research for this book and started dropping bread and pasta – and felt more comfortable eating butter and allowing red meat back into my diet – that I found that I could just effortlessly stay thin.
So that diet has clearly worked for me. It may not be right for everyone, but it is definitely the diet that has the most evidence to support it.
The Nutrition Coalition, which you head, is currently lobbying the U.S. government to only issue dietary guidelines henceforth that are based on rigorous science as opposed to ideology. What is the status of those efforts?
We’ve been working with whomever we can in government to take on this issue, and we feel buoyed by a really strong report from the National Academies of Sciences, Engineering and Medicine which came out last year and has quite a bit of language about how the government’s dietary guidelines lack scientific rigor. So that has opened up a lot of doors.
I don’t know how far we’ll get, but our goal is to try to have rigorous, evidence-based dietary guidelines by the year 2020, which is when the next dietary guidelines come out.
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