by Fred Provenza
In 2015, the Dietary Guidelines Advisory Committee (DGAC) issued a report with a striking recommendation: Eliminate dietary cholesterol as a nutrient of concern. This change astonished the public but is consistent with scientific evidence reporting no appreciable relationship between dietary cholesterol and serum cholesterol or clinical cardiovascular events in general populations. A less obvious change was the absence of an upper limit on total fat consumption. With this report, the DGAC reversed nearly four decades of nutrition policy that placed priority on reducing cholesterol and total fat consumption throughout the population. As with other scientific fields from physics to clinical medicine, scientists contend understanding of nutrition has advanced in recent decades.
Yet, despite the apparent increase in understanding obesity and diet-related diseases continue to rise. In 1960, fewer than 13 percent of Americans were obese, and fewer than 1,100 scientific articles were published on obesity and diabetes. Today, 49 percent of Americans are obese and the United States ranks number one among thirty-five nations in childhood obesity. In 2013, 44,000 scientific articles were published on these topics. In total, over 600,000 articles have been published alleging to provide worthwhile information on diet-related disorders.
The Government’s Bad Diet Advice
by Nina Teicholz
FOR two generations, Americans ate fewer eggs and other animal products because policy makers told them that fat and cholesterol were bad for their health. Now both dogmas have been debunked in quick succession.
First, last fall, experts on the committee that develops the country’s dietary guidelines acknowledged that they had ditched the low-fat diet. On Thursday, that committee’s report was released, with an even bigger change: It lifted the longstanding caps on dietary cholesterol, saying there was “no appreciable relationship” between dietary cholesterol and blood cholesterol. Americans, it seems, had needlessly been avoiding egg yolks, liver and shellfish for decades. The new guidelines, the first to be issued in five years, will influence everything from school lunches to doctors’ dieting advice. […]
In 2013, government advice to reduce salt intake (which remains in the current report) was contradicted by an authoritative Institute of Medicine study. And several recent meta-analyses have cast serious doubt on whether saturated fats are linked to heart disease, as the dietary guidelines continue to assert.
Uncertain science should no longer guide our nutrition policy. Indeed, cutting fat and cholesterol, as Americans have conscientiously done, may have even worsened our health. In clearing our plates of meat and eggs (fat and protein), we ate more grains, pasta and starchy vegetables (carbohydrates). Over the past 50 years, we cut fat intake by 25 percent and increased carbohydrates by more than 30 percent, according to a new analysis of government data. Yet recent science has increasingly shown that a high-carb diet rich in sugar and refined grains increases the risk of obesity, diabetes and heart disease — much more so than a diet high in fat and cholesterol.
My Beef With The AHA’s Saturated Fat Recommendations
by Larry Husten
Reading the new AHA paper I was struck by its extreme self-confidence, paralleled by its unwillingness to acknowledge the disastrous consequences of the last time the AHA pushed back against dietary fat and cholesterol. The result, as we all should know by now, was to unwittingly help unleash or at least contribute to the obesity and diabetes epidemics, as saturated fat and dietary cholesterol were replaced by carbs, often refined carbs, and sugar. Notably, the AHA took a long time to change its guidelines, and when it did those efforts were far less aggressive and received far less publicity than the original campaigns.
Now the memory of that catastrophe is fading, at least in some people who would rather forget it. In an article in Medscape one nutrition expert, defending the new AHA paper, offered the following quote: “But the AHA has always taken the stance that saturated fat is bad and that we should be eating more plant oils, and this view is endorsed by the vast majority of nutritionists who are scientifically qualified. [emphasis added]” He’s already forgotten that, in fact, in its earlier campaign the AHA did not explain that saturated fat should not be replaced with carbs, or even sugar.
The federal government on Thursday told Americans not to worry so much about cholesterol in their diets, that lots of coffee is fine and that skipping breakfast is no longer considered a health hazard.
The recommendations were part of a new “Dietary Guidelines for Americans,” the influential nutrition advice book that, updated every five years, expresses official thinking about what constitutes a nutritious meal.
In what may be the most striking change, the new version drops the strict limit on dietary cholesterol, stepping back from one of most prominent public health messages since the ’60s.
But there were several other notable changes. Salt limits were eased, if only slightly, for many people. Coffee won official approval for the first time, with the book saying that as many as five eight-ounce cups a day is fine. And apparently, skipping breakfast is no longer considered a health hazard: While the old version of Dietary Guidelines informed readers that “not eating breakfast has been associated with excess body weight,” the new version is silent on the topic. […]
Nevertheless, the new version seems inconsistent in places, or torn between new science and past recommendations.
For example, the new document dropped the warning about dietary cholesterol from its key recommendations and the document no longer calls for people to limit their cholesterol intake to 300 milligrams per day. This change was recommended by its own expert committee, which found that cholesterol is no longer “a nutrient of concern.”
But elsewhere in the report, the guidelines cite a 16-year-old report from the Institute of Medicine and advises people to “eat as little dietary cholesterol as possible while consuming a healthy eating pattern.”
Similarly, the report calls for people to limit the amount of saturated fat in their diet to 10 percent of their calories, and accordingly to choose milk and other dairy products that are no-fat or low-fat. But newer research, also cited by the guidelines, shows that merely reducing consumption of saturated fats may offer no benefit if people merely replace those saturated fats with carbohydrates, as they often do. […]
For all the debate, whether the guidelines have made American healthier is also a matter of debate. Critics have faulted the guidelines for failing to prevent the nation’s epidemic of obesity, and say major changes are necessary in the advice given.
“Given the same advice, it’s not clear why we should expect different outcomes, especially when consumption data shows that over the past decades, Americans have, in fact, followed USDA advice,” said Nina Teicholz, the author of Big Fat Surprise and a board member at the Nutrition Coalition, a new group, funded by Houston-based philanthropists Laura and John D. Arnold, lobbying for changes to the way the government develops dietary advice.
American Heart Association doubles down on outmoded saturated fat
by Dr. Ronald Hoffman
Are you suffering from health news whiplash? It seems lately that all the news has been about the how saturated fats have been exonerated—studies show that meat and high fat dairy contribute negligibly or not at all to the risk of heart disease.
In the face of all this new evidence, I’ve railed against the American Heart Association’s obdurate refusal to acknowledge that they were wrong. They continue to maintain, on their website and through their public pronouncements, that consumers should curtail their consumption of saturated fats and substitute instead polyunsaturated oils—corn, soy, and safflower.
A recent National Institutes of Health reviewshattered that premise: It showed that by swapping dietary saturated fats with vegetable oils, subjects indeed lowered their cholesterol. But that cholesterol reduction didn’t translate into protection against atherosclerosis, heart attacks or death from all causes.
But last week, to my astonishment, the American Heart Association reiterated its position: Its “Presidential Advisory on Dietary Fats and Cardiovascular Disease” states “Lower intake of saturated fat and coupled with higher intake of polyunsaturated and monounsaturated fat is associated with lower rates of cardiovascular disease and of other major causes of death and all-cause mortality.” The magnitude of this protective effect is estimated to be a whopping 30%, comparable to the use of statin drugs [irony intended!].
This is reminiscent of the way a religious orthodoxy, whose authority might be threatened with facts that undermine its cherished dogma, would fight back with renewed vigor: Science declares, “The earth is round.” Counter this heresy by delivering a pronouncement that, indeed, the earth is flat. Order it proclaimed from every pulpit.
The Big Fat Surprise
by Nina Teicholz
Taken together, these trials have shown that the low-fat diet has at best proved ineffective against disease and at worst aggravated the risk for heart disease, diabetes, and obesity. The standard, AHA-prescribed low-fat diet has consistently failed to produce better results for health than diets higher in fat.
A review in 2008 of all studies of the low-fat diet by the United Nation’s Food and Agriculture Organization concluded that there is “no probable or convincing evidence” that a high level of fat in the diet causes heart disease or cancer. And in 2013 in Sweden, an expert health advisory group, after spending two years reviewing 16,000 studies, concluded that a diet low in fat was an ineffective strategy for tackling either obesity or diabetes. Therefore, the inescapable conclusion from numerous trials on this diet, altogether costing more than a billion dollars, can only be that this regime, which became our national diet before being properly tested, has almost certainly been a terrible mistake for American public health.
“It is increasingly recognized that the low-fat campaign has been based on little scientific evidence and may have caused unintended health consequences,” wrote Frank Hu, a nutrition professor at the Harvard School of Public Health, in 2001. With this growing pile of evidence on the table, health authorities clearly see the need to update their advice. Yet they are understandably reluctant to reverse course too loudly on fifty years of nutrition recommendations, and this hesitance has led to a certain vagueness on the subject. The USDA and AHA have both quietly eliminated any specific percent fat targets from their most recent lists of dietary guidelines. Those 30–35 percent fat targets that we’ve abided by for decades? They’re now gone. And so is, actually, any discussion of the topic in their reports. How much fat should we be eating? These groups now don’t say, and this silence on the issue—it must be said—does not seem like the clear, confident leadership from our authorities that we might like to see on the subject of how we should eat to fight the major diseases of our time.
Of course many of us who’ve been paying attention to the science have been welcoming fat back into our diets for some time already. We’ve given up spraying with Pam, stopped poaching, and started using salad dressings again. And if there’s a silver lining to those low-fat years, it’s this: we learned that fat is the soul of flavor. Food is tasteless and cooking nearly impossible without fat. Fat is essential in the kitchen to produce crispness and to thicken sauces. It is crucial in conveying flavors. It makes baked goods flaky, moist, and light. And fat has many other, essential functions in cooking and baking. To satisfy all these compelling needs, nutrition experts coming out of the low- to nonfat 1980s and looking for a solution found one apparently perfect candidate: olive oil. And that is one of the reasons why, in the early 1990s, the “Mediterranean Diet” entered the picture.
Americans have dutifully followed official dietary advice to restrict fat and animal products for more than sixty years now, ever since the AHA first recommended this diet in 1961 as the best way to avoid heart disease and obesity. Nineteen years later, in 1980, the USDA guidelines joined in. Since then, the government’s own data shows that Americans have reduced their consumption of saturated fat by 11 percent and overall fat by 5 percent. XXXIV Red meat consumption has steadily declined, replaced by chicken. According to a USDA report, Americans also complied with official advice to lower the dietary cholesterol found abundantly in egg yolks and shellfish, even though the cholesterol in food has long been known to have little impact on serum cholesterol (as discussed in Chapter 2). XXXV The original rationale for cutting back on fat was to lower serum cholesterol, and Americans have successfully done that, too. Since 1978, total cholesterol levels among US adults have fallen from an average of 213 mg/dL down to 203 mg/dL. The portion of Americans with “high” cholesterol (over 240 mg/dL) has dropped from 26 percent to 19 percent. Moreover, most of that drop has been due to declines in LDL-cholesterol, the target most emphasized by officials for the past thirty years. In 1952, when Ancel Keys first started arguing for the reduced-fat diet, he predicted that if “mankind stopped eating eggs, dairy products, meats and all visible fats,” heart disease would “become very rare.” This has certainly not been the case.
Indeed, during these years, and despite or perhaps because of these efforts, Americans have experienced skyrocketing epidemics of obesity and diabetes, and the CDC estimates that 75 million Americans now have metabolic syndrome, a disorder of fat metabolism that, if anything, is ameliorated by eating more saturated fat to raise HDL-cholesterol. And although deaths from heart disease have gone down since the 1960s, no doubt due to improved medical treatment, it’s not clear that the actual occurrence of heart disease has declined much during that time.
Authorities are naturally reluctant to take responsibility for this outcome. The same recent USDA report that documents the public’s success in adhering to its dietary guidelines nevertheless places the onus of blame for obesity and disease squarely on American children and adults, “very few” of whom “currently follow the US Dietary Guidelines”—an unsubstantiated assertion that is repeated throughout the report.
The dietary recommendations now offered by the USDA and AHA for solving the nation’s health problems are basically: stay the course. Both groups have backed off their limits on fat slightly. The most recent set of AHA dietary guidelines shifts its dietary fat recommendation from a limit of 30 percent of calories to a range of between 25 percent and 35 percent, arguably a meaningless change to most people. And the USDA’s latest Dietary Guidelines, published in 2010, scrapped any specific percentile targets for the three main macronutrient groups, protein, fat, and carbohydrates, altogether. XXXVI Yet the prohibitions against saturated fats remain strong, and the USDA report continues to take the stance that “healthy diets are high in carbohydrates.”
Meanwhile, the same biases that have sustained the diet-heart hypothesis for so many decades remain, and those biases continue to steer the nutrition conversation every step of the way. So, in 2006, when the Women’s Health Initiative reported that a low-fat diet made no difference to disease or obesity, the WHI investigators, as well as officials at the AHA and NHLBI, issued press releases stating that this half-a-billion-dollar study had not been conducted well enough to make any conclusions about changing our diets. In 2010, when Krauss’s metanalysis came out with good news about saturated fats, the American Journal of Clinical Nutrition minimized its impact by publishing the critical editorial by Jerry Stamler as an “introduction” to Krauss’s work. And inconvenient findings, such as those by Volek and Westman, continue to be ignored, reasoned away, or misinterpreted by the great majority of nutrition experts.
Moreover, the alliance between the media and the nutrition mainstream endures. Mark Bittman, a food columnist at the New York Times , is perhaps the most prominent example of a voice in the media encouraging a diet based on fruits and vegetables while minimizing meat, a mantle he inherited from Jane Brody. Journalists and nutrition authorities also continue to dovetail in amplifying any study finding that appears to condemn either red meat or saturated fat. XXXVII And the public gets the message. Americans continue to avoid all fats: the market for “fat replacers,” the foodlike substances substituting for fats in processed foods, was, in 2012, still growing at nearly 6 percent per year, with the most common fat replacers being carbohydrate-based. XXXVIII
If, in recommending that Americans avoid meat, cheese, milk, cream, butter, eggs, and the rest, it turns out that nutrition experts made a mistake, it will have been a monumental one. Measured just by death and disease, and not including the millions of lives derailed by excess weight and obesity, it’s very possible that the course of nutrition advice over the past sixty years has taken an unparalleled toll on human history. It now appears that since 1961, the entire American population has, indeed, been subjected to a mass experiment, and the results have clearly been a failure. Every reliable indicator of good health is worsened by a low-fat diet. Whereas diets high in fat have been shown, again and again, in a large body of clinical trials, to lead to improved measures for heart disease, blood pressure, and diabetes, and are better for weight loss. Moreover, it’s clear that the original case against saturated fats was based on faulty evidence and has, over the last decade, fallen apart. Despite more than two billion dollars in public money spent trying to prove that lowering saturated fat will prevent heart attacks, the diet-heart hypothesis has not held up.
In the end, what we believe to be true—our conventional wisdom—is really nothing more than sixty years of misconceived nutrition research. Before 1961, there were our ancestors, with their recipes. And before them, there were their ancestors, with their hunting bows or traps or livestock—but like lost languages, lost skills, and lost songs, it takes only a few generations to forget.
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