In the 80s policymakers look to what had worked before on a different public health menace smoking. Back in 1964 the Surgeon General’s Office published a landmark report that established a link between smoking and cancer. In the following years, rates of smoking fell dramatically and tobacco related cancer started declining. It was a watershed moment in public health and the report was widely credited with helping to save millions of lives. So to try and recreate some of that success in 1988, the Surgeon General’s Office published a 700 page report to help fix our diet. The Surgeon General boasted that the depth of the science was even more impressive than the legendary smoking study. It was the first time officials identified the reduction of fat as the number one dietary priority. And when the USDA food pyramid came out four years later, it reflected that fat was crammed into the tippy-top along with a warning to only use it sparingly, whereas a host of carbohydrate-rich foods occupied the pyramids wide bottom layer. The message it sent was simple and clear: carbohydrates good fat bad. The food pyramid spread far and wide. It was in schools, on posters, in our homes, and on our minds. It was the most widely adopted guideline for healthy eating in the history of the United States. Over a decade after it came onto the scene, a Gallup survey found that 82 percent of Americans believe the pyramid was the basis of a sensible, healthful eating plan. But despite the pyramids notoriety in years of educating the public about nutrition, Americans didn’t seem to be getting any healthier obesity and diabetes were continuing to climb. So what was going on?Well, first of all it turns out that the food pyramid’s use fat sparingly caution was an oversimplification from the start. Research today makes a pretty strong case that not all fats are created equal. And some fats are actually good. In fact two little good fat could actually be leading to heart disease and obesity. The very problems the food pyramid had been developed to prevent. And the problems with oversimplification didn’t end there. The wide bottom of the pyramid gave many the impression that eating a diet with lots of carbs was good. Without distinguishing between complex carbs found in whole grains and oats, and simple carbs found in things like white bread and baked goods which her body quickly turns into waste-expanding sugar. The pyramid’s authors actually knew this at the time. But they thought keeping their guidelines simple was important, so they left that part out. And the decision proved to be a fateful one. The pyramids low-fat, high-carb recipe would end up contributing to a low-fat diet craze that was about to sweep the nation. Sensing the growing anti-fat sentiment in the 80s and 90s the food industry responded by developing thousands of reduced fat products. Yogurt, chips, meats, cheeses, and cookies. By 2005 low-fat and fat-free products were a thirty-five billion dollar market. The largest segment of the diet food industry, but there was a catch. When food manufacturers took out the fat. They had to replace it with something that still made it taste good, which almost always meant adding extra sugar and carbohydrates. Compared to the late ’70s, today we eat around 60 more pounds of grains and 30 more pounds of sweeteners every year. At the same time, we’re eating up to 400 more calories per day in recent years. There are signs that perspectives are changing. In 2015 the official dietary guidelines eliminated its limits on cholesterol. And the American Heart Association has gradually revised its guidelines, and moved away from its strict guidance to lower fat intake.
The bottom line is that nutrition is complex. And despite collective efforts of some of the plantiffs best minds, the science of nutrition is still young and evolving. The number of annual studies on obesity and diabetes alone has risen from about 1, 000 in 1960 to 44, 000 in 2013. It’s likely that more than a million articles have been published on dieting over the last 50 years.