The goal of the federal government’s Dietary Guidelines for Americans is to provide simple advice that promotes nutritional health, but for millions of Americans it may do exactly the opposite. The recommendations, issued by the U.S. Department of Agriculture (USDA), may appear harmless. There remains, however, little evidence that the Guidelines have helped reduce obesity in America and some evidence that it may actually have made it worse. The guidelines may also have adverse consequences for those with restrictive eating disorders (RED). So we should ask the question: is it time to end the Dietary Guidelines for Americans?
While the “obesity epidemic” is a major issue in public health, Congress’s original goal in developing dietary recommendations for the country was to reduce malnutrition. Perversely, the recommendations in the guidelines may promote malnutrition in certain people. An estimated two million adults suffer from anorexia or bulimia nervosa according to the National Institute of Mental Health. Two million more adults engage in restrictive eating behaviors, though aren’t clinically classified as having a disorder consistent with the stringent diagnostic criteria for recognized eating disorders. A common feature which these distinct disorders share is in the restriction or expulsion of certain foods and nutrients. The guidelines seem to encourage this behavior in individuals with RED. This apparent validation of restrictive eating may actually exacerbate the disordered behaviors of those afflicted by such conditions.
From their inception, political interests influenced the guidelines more than robust, scientific evidence. First issued by the USDA in 1980, the DGA contained seven broad recommendations, among which were that Americans should avoid “too much” fat, saturated fat, cholesterol, sugar, and sodium. These recommendations were based not on scientific literature or consensus, but on the opinions of politically-connected and ideologically-favored “experts” invited to testify before Sen. George McGovern’s (D-SD) Senate Select Committee on Nutrition and Human Needs.
In the decades that followed, the evidence has continuously revealed the unsound basis for those recommendations. The advice to limit dietary cholesterol intake—because it was believed to increase cholesterol in the blood—is the most famously debunked. But there is increasing controversy over most of the other recommendations, including restricting fat and sodium. Even the idea that sugar alone causes obesity has been challenged by studies showing that overall calories (regardless of sugar intake) matter far more and that sugar is, in fact, an important part of a balanced diet.
If there is uncertainty over how the DGA affects generally healthy individuals, there is even less evidence about their effect on those with disordered eating. In 1997, eating disorder specialist and physician Steven Bratman coined the term “orthorexia nervosa” to describe a condition where people adhere to extreme diets. It is estimated that just under 1% of the adult population shows signs of orthorexia. This obsession with “clean eating” can, ironically, result in malnutrition, illness, and life-threatening conditions. A severely restricted diet can lead to deficiencies in essential vitamins, minerals, and nutrients, putting individuals at risk of a range of medical complications that are similar to those seen in patients with anorexia such as anemia, depressed heart rate, and bone disorders. For example, too little sodium may lead to hyponatremia (sodium deficiency) and cerebral edema (swelling of the brain) while too little fat in the diet may limit absorption of fat-soluble vitamins which are essential for bone development. Individuals with bulimia, on the other hand, develop sometimes irreversible gastrointestinal, esophageal, and cardiopulmonary problems.
A difficulty of treating RED is that most who suffer fail to seek treatment. The few who do frequently drop out because they reject that they have a problem to begin with. The challenge of treating those with orthorexia is magnified because the disease is less recognized and sufferers believe they are promoting their health by their behavior. State-sanctioned advice to restrict or avoid certain foods and nutrients may give those with RED reason to justify their warped restrictive and compensatory behaviors, seeing as how the foods that these individuals fear are those that the USDA cautions against eating.
The potential of the DGA to exacerbate complications of those who suffer as profoundly as do those with RED warrants investigation. The recommendations were never based on sound science, may have little benefit to the general population, and completely overlook the interests of the large numbers of people in need of individualized nutritional guidance. It may therefore even be time for the government to get out of the business of making dietary recommendations altogether.