Читать книгу The Human Race – Too Smart to Survive онлайн

34 страница из 42

In 1849, Thomas Addison wrote of a potentially fatal anemia called “pernicious anemia”. It was characterized by reduced but enlarged red blood cells. Vitamin B12 was later identified as the missing element, but absorption in the intestines is only possible through an “intrinsic factor” found in the stomach and intact gastric acid, both products of intact gastric cell metabolism.

Beriberi was a disease not uncommon in rice-rich Asian cultures in the 19th century, characterized by fatigue, impaired concentration, tremors, abdominal pain, burning of the feet, and even paralysis and heart failure. On longer sea voyages, up to 60% of the crew became ill and 25% died. Both deaths and the onset of the disease were prevented entirely by the introduction of barley, milk, beef, and tofu. At first, it was speculated that the increase in protein intake made the difference. In further studies, the link between white and brown rice was established. 70% of prison inmates became ill with white rice as their main food source, while only 3% of inmates with brown rice in their diet became ill. In 1906, Norwegian bacteriologist Axel Holst found that symptoms in hamsters disappeared simply by feeding them cabbage and lemon juice. In the same year, Frederick Gowland Hopkins conducted an experiment on two groups of rats that were fed different diets. One group was fed casein, fat, starch, sugar and salt (essential nutrients known up to that time), the other group was additionally fed milk. Only the group supplemented with milk thrived. As a result, it was assumed that this disease was also due to a substance deficiency. In 1912, Casimir Funk researched the substances that were thought to be causative for the various diseases and called them “vital amines.” The word vitamin came into being in 1920, when it became known that not all vitamins contain amines.10 Funk was able to assign the individual vitamins to the various diseases, so that there was now a scientific explanation for the development of diseases due to a lack of nutrients. Other diseases such as scurvy (vitamin C deficiency) and rickets (vitamin D deficiency) could now be explained. Vitamin D deficiency was especially prevalent in cities during industrialization when people, especially the poor and children, had to work in coal-fired power plants and underground. Vitamin A was initially identified as the factor that caused the disease, but in 1922 it was discovered that the molecule originally called vitamin A consisted of a second co-factor: vitamin D.