Nearly two decades ago, the U.S. Department of Agriculture (USDA) created a powerful icon: the Food Guide Pyramid. This simple illustration conveyed in a flash what the USDA said were the elements of a healthy diet. The Pyramid was taught in schools, appeared in countless media articles and brochures, and was plastered on cereal boxes and food labels.
Tragically, the information embodied in this pyramid didn’t point the way to healthy eating. Why not? Its blueprint was based on shaky scientific evidence, and it barely changed over the years to reflect major advances in our understanding of the connection between diet and health.