In mid-February, the government released a scientific report that will shape its 2015 Dietary Guidelines for Americans. Think of it as America's basic nutrition policy. Most people who read the report would have viewed it as a snore; not much has changed.
Yes, the report lifted the longstanding advice to limit cholesterol in foods. That boils down to dropping advice to limit egg yolks. Liver is high in cholesterol, but rarely eaten. Shrimp is high in cholesterol, but so low in saturated fat -- the prime driver of high blood cholesterol -- that its cholesterol hardly matters.
Indeed, most of the report's advice -- to eat less saturated fat, sugar, and salt, and to eat more whole grains, fruits, and vegetables -- has not changed since the first guidelines were issued in 1980.
But that didn't stop some critics from using the report to drum up publicity for their own fringe views on diet and health. A case in point: Nina Teicholz, author of The Big Fat Surprise, wrote an op-ed in The New York Times entitled "The Government's Bad Diet Advice." Unfortunately for Times readers, the op-ed was packed with errors and distortions.
Teicholz: "Last fall, experts on the committee that develops the country's dietary guidelines acknowledged that they had ditched the low-fat diet."
Fact: The Dietary Guidelines last recommended a "low-fat" diet in 1995. (And that diet got up to 30 percent of its calories from fat -- which is just slightly less than what Americans have eaten for years.)
The new report wisely emphasizes not just nutrients, but foods. It recommends diets that are "rich in vegetables, fruit, whole grains, seafood, legumes, and nuts; moderate in low- and non-fat dairy products and alcohol (among adults); lower in red and processed meat; and low in sugar sweetened foods and beverages and refined grains."
Teicholz: "How did experts get it so wrong?...The primary problem is that nutrition policy has long relied on a very weak kind of science: epidemiological, or 'observational,' studies in which researchers follow large groups of people over many years."
Fact: The new report, like its predecessors, relies on both observational studies and clinical trials. (Note: It is rather presumptuous for anyone to brand the entire field of epidemiology as "weak.") What's more, Teicholz's book cites observational studies that support her views.
Teicholz: "In 2013, government advice to reduce salt intake (which remains in the current report) was contradicted by an authoritative Institute of Medicine study."
Fact: The 2013 IOM report found insufficient evidence showing that very low sodium intakes prevent cardiovascular disease to recommend lowering sodium to 1,500 milligrams a day, but it did not contradict advice to reduce salt intake.
Teicholz: "Several recent meta-analyses have cast serious doubt on whether saturated fats are linked to heart disease, as the dietary guidelines continue to assert."
Fact: Meta-analyses can be flawed. For example, one of Teicholz's favorites concluded that saturated fats do not cause heart disease, but that was only because it included a study in which people replaced saturated fats with a margarine high in trans fat instead of heart-healthy oils. That's why the public is wise to rely on advice from expert panels that sort through the details. In 2013, experts convened by the American Heart Association and the American College of Cardiology did that. Their conclusion: we should cut saturated fat even further than earlier guidelines had recommended.
Teicholz: "In clearing our plates of meat, eggs and cheese (fat and protein), we ate more grains, pasta and starchy vegetables (carbohydrates)."
Cleared our plates? Since 1970, cheese consumption has tripled, eggs have dropped just 20 percent, pork has held steady, and we've replaced only a third of our beef with chicken. Yes, refined flour increased, but that's because we've been eating oversized portions of pizza, cheeseburgers, sandwiches, burritos, bagels, wraps, cookies, cupcakes, scones, muffins, doughnuts, waffle cones, soft pretzels, and more. We can thank our food companies and restaurants -- not any government dietary advice -- for that.
Teicholz: "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."
Fact: According to the National Health and Nutrition Examination Survey, the average American ate as much fat (about 80 grams a day) in 2010 as in the early 1970s, when the survey started. Because we're eating more calories overall (largely from refined flour and sugar), a slightly smaller percentage of our calories (33 percent instead of 37 percent) comes from fat.
At least that's what people say they eat. According to USDA data, which estimates how much we eat by tracking data on how much is produced (after adjusting for waste), consumption of "added fats and oils and dairy fats" climbed since 1970. That should come as no surprise. French fries, fried chicken, potato chips, nachos, and movie theater popcorn haven't exactly gone out of style.
Teicholz: "The committee's new report also advised eliminating "lean meat" from the list of recommended healthy foods."
Fact: Eliminated? The report recommends a diet "lower in red and processed meat" and noted that "lean meats can be a part of a healthy dietary pattern."
Teicholz: "Since the very first nutritional guidelines to restrict saturated fat and cholesterol were released by the American Heart Association in 1961, Americans have been the subjects of a vast, uncontrolled diet experiment with disastrous consequences."
Fact: Between 1968 and 2008, heart disease deaths plummeted by 75 percent. Those gains -- which were due to better diet, better drugs, and better treatment -- are hardly a disaster.
True, we are now faced with an obesity epidemic and the ensuing rise in diabetes rates. But where's the evidence that diet advice is to blame?
Americans did not gain weight because of advice to eat less fat. We can blame the obesity epidemic on a diet of super-sized cheeseburgers, fries, shakes, pizza, fried chicken, burritos, cheese nachos, chocolate-dipped waffle ice cream cones, movie theater popcorn (by the bucket), cookies, muffins, cupcakes, doughnuts, and more. And, of course, soft drinks, energy drinks, sports drinks, fruit drinks, and other sugar-sweetened beverages deserve special recognition for expanding the average American's waistline.
Surely, no one would argue that advice from the government had more impact than multi-million-dollar campaigns for Coca-Cola, Pepsi, Gatorade, McDonald's, Burger King, Taco Bell, KFC, Pizza Hut, Domino's, Dairy Queen, Sonic, Dunkin' Donuts, and more.
And it's not just fast food. A typical entrￃﾩe at most sit-down restaurant chains like Applebee's, California Pizza Kitchen, Chili's, Maggiano's Little Italy, Outback Steakhouse, T.G.I.Friday's, Romano's Macaroni Grill, and Uno Pizzeria & Grill has about 1,000 calories. At chains like The Cheesecake Factory, many entrￃﾩes have 2,000 calories. And that doesn't include another 1,000 or so calories each for the appetizer and dessert.
Here's the kicker: If the guidelines were powerful enough to prompt increased consumption of high-sugar foods, why wouldn't the guidelines' advice (since 1980) to eat less sugar have halted the rise in sugar consumption?