The US Department of Agriculture (USDA) released the Food Guide Pyramid in 1992, but much of the nutritional advice it offered has since been debunked.
The pyramid made no distinction between refined carbs like white bread and whole grains like brown rice. There is also no distinction between the healthiest proteins (like beans, nuts, and fish) and red meat, which can increase one's risk of cancer and heart disease.
The chart also banished healthy fats to the "use sparingly" tip of the pyramid, lumping them in with added sugars and trans fats from processed oils and packaged foods. However, in the mid-1990s, Harvard researchers estimated that trans fats led to roughly 50,000 preventable deaths each year in the US. And research shows that the healthy unsaturated fats found in foods like nuts, seeds, and avocados are crucial to a balanced diet.