The concept of nutrients has existed since the early nineteenth century, when the English physician and chemist William Prout identified the three main components of food: proteins, lipids, and carbohydrates, later referred to as "macro-nutrients". Justus von Liebig, the great German scientist, considered one of the founders of organic chemistry and modern science of nutrition, added a couple of minerals and declared the mystery of animal nutrition solved. Later, Liebig invented a meat extract that has been developed into what we now use as a stock cube, and the first infant formula, based on cow's milk, flour, malt, and potassium bicarbonate. However, doctors soon realised that many babies who only drank the formula milk made according to Liebig's recipe struggled to grow.
In addition, sailors along ocean routes often got sick despite getting enough protein, carbohydrates, and lipids. Evidently, the chemical scientists had underestimated something: the presence of some essential ingredients in fresh plant foods that were capable of healing sailors. At the beginning of the twentieth century, this observation led to the discovery of the first group of micro-nutrients, which, in 1912, the Polish biochemist Casimir Funk called "vitamins". These special molecules almost miraculously cured diseases such as scurvy or beriberi, and from the 1920s they became fashionable among the bourgeoisie.
