Amanda K. Beck, A reference hand-book for nurses (1919)
“ Protein, fats, carbohydrates, mineral salts, and water are the compounds we need in our foods, and they are found in flesh foods and vegetables. Protein, the most important element, is derived principally from meat, eggs, and milk. It is also furnished by some vegetables, as beans, peas, and the gluten of wheat; but in these it is mixed with too much extraneous matter, as husks, bulbs, woody fiber, etc., to be useful in the diet of the sick. Extractives, as beef-tea, are included in the nitrogen compounds, but they neither build tissue nor furnish energy; they are appetizers and stimulants. ”
