In older nutritional writing, a term for starchy, non-nitrogenous foods, meaning foods composed chiefly of carbohydrate with little protein, since nitrogen was the marker of protein. Bread, potatoes, and rice were classic amyloids in this classification, contrasted with nitrogenous foods like meat and eggs. The word has since been almost entirely captured by medicine, where amyloid denotes the abnormal protein deposits of amyloidosis and Alzheimer’s disease, a completely different meaning that causes confusion when old texts are read today. Encountering amyloid in a nineteenth-century diet book means starch; encountering it in a modern journal means misfolded protein. The shift illustrates how scientific vocabulary migrates, and why historical nutrition literature needs translation for modern readers.