Over the past few years, an inaccurate story about food and public health has gained momentum. Food writers and some reputable academics have been touting a cautionary tale about obesity that blames the nation’s poor health on nutrition scientists. The “Snackwell effect” posits that back in the 1980s and 1990s, the Dietary Guidelines for Americans and many well-meaning nutrition experts told everyone to eat less fat, and the American public responded by replacing fat with more refined carbohydrates, especially sugar (in the form of low-fat snack foods like Snackwell’s cookies), and the results were disastrous, producing the obesity epidemic.
Belief in this oft-repeated story is convenient. It poses nutrition academics as the sadly misguided villains, with the general public as their unwitting victims. News and opinion stories on the subject often rank among the most popular when published, reflecting keen public interest. So what’s the problem? One problem is that the story is wrong on the facts. Another problem is that the story is a damaging distraction, obscuring the real causes of — and solutions for — diet-related, preventable disease.
The evidence for the narrative is circumstantial — that is, advice to eat less fat occurred around the same time as the obesity epidemic took off — but the factual errors in this story are many. For starters, we never cut our fat intake. While the food industry did introduce a wave of low-fat cookies, cakes, chips, and other snack foods in the 1990s, the “low-fat craze” didn’t last long. (By 1999, fat was coming back into those same foods, and that trend was followed by a “low-carb craze” in the early 2000s.) More importantly, the “low-fat craze” never led the average person to eat less fat. Depending on whether you look at data that keeps track of what is produced or surveys that ask people what they eat, fat consumption has either increased or stayed fairly constant since 1980. Instead, calories — especially from white flour and added sugar — increased markedly.
Starting in 1980, the Dietary Guidelines and nutrition experts also told us to eat less added sugars. It should be unsurprising that eating Snackwell’s — or other sugary foods without any nutritional benefit — has never been considered sound dietary advice. Proponents of the Snackwell blame-game tend to conveniently overlook the fact that the advice to reduce sugar was mostly ignored during the same period that we were all supposedly dutifully following advice on fat. In fact, in 1999, just 10 percent of Americans ate a healthy diet consistent with federal nutrition recommendations.
The fact that we started eating more added sugar just when experts told us to eat less is a clue. The nutrition scientists who do the long, hard slog of working out details of official dietary advice might only dream of the life-altering powers now being attributed to them. The public has never eaten the diet they recommend, and still does not today. Various editions of the Dietary Guidelines for Americans were largely consistent in their advice for decades — emphasizing diets higher in fruits, vegetables, and whole grains, and lower in added sugars, sodium, and saturated fats. Yet there remains a major disconnect: as the 2015 Committee’s analysis made clear, a full one-third of our national diet is comprised of burgers, sandwiches, pizza, dessert, sweet snacks, and sugary beverages.
So what did cause the obesity epidemic? A prime culprit is the number of excess calories now available to us, especially outside the home — not just in restaurants, but in gas stations, drug stores, convenience stores, and other places, which comprise what some call our “toxic food environment.” The number of U.S. eating establishments increased by 75 percent between 1977 and 1991, about the same time obesity rates started to climb. In the late 1970s, we consumed 18 percent of our calories outside the home. Now, it’s 32 percent.
What’s more, portion sizes of some popular restaurant or bakery foods rose sharply in the 1980s and continued to grow, and many restaurant meals are too large. At a variety of restaurants (American, Chinese, Italian, Mexican, Indian, Thai, Japanese, Greek, and Vietnamese), a typical entree has about 1,300 calories. And that’s without appetizers or desserts, which often have another 1,000 calories each. A recent Cochrane Collaboration analysis concluded that people consistently consume more food when offered larger portions. What’s more, portion sizes outside the home are a major source of “nutrition education” likely to influence what we eat at home.
And then there is the type of calories we consume. Much of the rise in refined-sugar consumption since 1980 (which peaked in 1999 and declined since) came from sodas, sports and energy drinks, counter to dietary advice but consistent with the ubiquity of these drinks and their billion-dollar marketing budgets. In addition, overall calories climbed, thanks largely to the white flour in bigger pizzas, tortillas, hamburger buns, cookies, cakes, doughnuts, and the like. In short, up against the onslaught of advertising dollars and the tempting array of convenient, high-calorie choices, we are often hard-pressed to follow sensible diet advice. Walk into any convenience store, or look at the checkout aisles in virtually any retail establishment. Profit, convenience, and cost — not nutrition science — are the driving forces influencing a vast majority of the food choices made by Americans.
The costs of this unhealthy situation are stunning. Two-thirds of American adults, and one in three young people, are obese or overweight, increasing their risk of heart disease, high blood pressure, type 2 diabetes, arthritis-related disability, and cancer. A 2005 CDC study linked 112,000 deaths to obesity each year — the equivalent of a jetliner filled with 300 passengers crashing every day.
The real problem, then, with the Snackwell myth is that it changes the subject from the actual culprits — the food industry that creates, and benefits from, this smorgasbord of bad options — to a scuffle over scientific uncertainty. As in so many cases of manufactured doubt, it also helps the food industry by suggesting the science underlying advice on public health is far more arbitrary and politicized than it is. Yet that, too, is wrong: with regard to the big picture, the (admittedly dull) history is that the government has issued basically the same dietary advice for the past 30 years.
Few things are less trendy than the truth. But it would be folly for well-intentioned foodies or journalists with an agenda to continue filling column inches without a more thorough examination of the underlying facts. Our diet, sadly, is not health-promoting, and our constructed food environment has only gotten more hazardous over the past few decades.
Instead of engaging in such distractions, we should take full advantage of recent improvements by changing the context in which we make choices. Dietary advice is far less influential than shifts that put a thumb on the scale for health — like more fruits and vegetables (and less sugar and salt) in school lunches, or better labeling of the added-sugars content in foods, or the recent move to ban trans fat from the diet altogether. A modest tax on sugary drinks would be a hundred-fold more effective in reducing sugar consumption than any government report could possibly be.
Such hard-fought interventions, not man-bites-dog theories, are where changes get made that will save lives and prevent the suffering of millions of people. They are, sometimes literally, the low-hanging fruit. There is so much more we could do to improve our food environment in the name of health, if we could simply work together to make the healthier choices the easier ones to make.