The Politics of Dietary Recommendations

The U.S. government has issued dietary recommendations for more than a century, but its advice did not become controversial until the 1970s. This history reflects changes in agriculture, food product development, and international trade, as well as in science and medicine. In 1900, the leading causes of death were infectious diseases, such as tuberculosis and diphtheria. These conditions were fostered by the nutrient deficiencies and overall malnutrition prevalent at the time, especially among the poor. Life expectancy at birth for both men and women barely exceeded forty-seven years (in 2007, it was seventy-eight years). To improve public health, government nutritionists advised the public to eat more of a greater variety of foods. The goals of health officials, nutritionists, and the food industry were much the same—to encourage greater consumption of the full range of American agricultural products. Throughout the twentieth century, an expanding economy led to improvements in housing, sanitation, and nutrition, and diseases related to nutritional deficiencies declined. By the 1970s, health officials were well aware that the principal nutritional problems had shifted: they were now conditions associated with overnutrition—eating too much food or too much of certain kinds of food. Overnutrition causes a different set of health problems; it changes metabolism, makes people overweight, and increases the likelihood of chronic diseases, such as coronary heart disease, certain cancers, diabetes, hypertension, stroke, and others—the leading causes of illness and death among any overfed population. With this shift in dietary intake and disease patterns, nutritional recommendations also had to change. Instead of promoting “eat more,” the advice of nutritionists shifted to emphasize eating less of certain dietary components—or of food in general. Advice to eat less, however, runs counter to the interests of food producers. Hence: politics.