The discovery that shook medical thinking

The discovery that shook medical thinking

Vitamins, vitamins, vitamins. They’re everywhere: Vitamin water, vitamin supplements. antioxidant-rich (read: vitamin-rich) superfoods.

These little micronutrients are fundamental to our health and the prevention of disease. This we now know. However, this hasn’t always been the gospel. Clues that vitamins are integral to our nutrition started to appear throughout the 18th century, but the majority of the footwork occurred between the early 19th century and the mid-20th century. The progress, however, was not all smooth sailing. There were plenty of setbacks and controversy along the way.

The fact that a lack of micronutrients (what we now know as vitamins) could cause illness went against all the thinking at the time – that the only cause of disease was due to micro-organisms, or ‘germs’.

The clue that pathed the way

Gelatin was supposed to be more than the main marshmallow ingredient. It was supposed to be the solution to hunger and poverty in France. In the early 18th century, chemists worked out how to extract the gelatin from leftover bones, and philanthropists wanted to use the compound to feed the poor. The idea, however, went down as well as Oliver Twist’s request for a second bowl of soup.

Nonetheless, the Gelatin Commission Committee wanted to know whether gelatin held nutritional value. François Magendie (1783-1855), the pioneer of experimental physiology, asked two questions that were the precursor for vitamin research. He questioned whether non-protein foods held any nutritional value and whether gelatin represented a complete source of protein. The physiologist used his dogs as lab rats and fed them a diet free of protein, e.g. of sugar, gum arabic. The health of his dogs deteriorated – their symptoms resembled what we now know to be a vitamin A deficiency.

Germ theory – the rival dogma

In a time when scientists were none the wiser, micro-organisms were considered the sole perpetrators of human illness. Louis Pasteur (1822-1895) and Robert Koch (1843 – 1910) led the Germ Theory, which was backed up by the discoveries of the micro-organisms behind diseases such as anthrax, malaria, and tuberculosis.

There were, however, holes in the theory. Scientists could not identify the microorganism-malefactor of some diseases, such as scurvy and beriberi, but still implicated them as a cause. For example, Christiaan Eijkman (1858-1930) noticed that his chickens, fed only on processed rice (bran-devoid rice), developed polyneuritis, a condition that affects the peripheral nervous system. Blinded by the Germ Theory, he concluded that polished rice holds germ-related toxins, but the bran neutralizes the mystery toxin.

Others were brave enough to look outside the Germ Theory box. Gerrit Grijns (1865-1944) expanded on Eijkman’s research, and, through the testing of several food types, concluded that, what is now known as human beriberi – a vitamin B1 deficiency-related disease that is caused by a nutrient-related deficiency. Grijns managed to persuade Eikman, but he failed to convince the rest of the world as he communicated his findings in Dutch.

The vitamin theory

Frederick Gowland Hopkins (1861-1947) voiced what many scientists had found – that animals and humans alike are unable to thrive on fat, proteins, carbohydrates, and inorganic minerals alone. Through experimentation, Nicolai Lunin (1853-1937) found milk contained a substance critical for mice development and growth, and Carl A. Socin found that egg contained a material necessary to all life. The experimentations by Wilhelm Stepp (1882-1964) confirmed that mice relied on a mandatory, fat-soluble component in milk. For lack of a better term, Stepp dubbed the unknown element an accessory factor. Casimir Funk (1884-1967) decided on another name for the mystery substances: vitamins. Both describe what we now know as vitamins.

A credit to the scientists

During the 19th century, scientists isolated and synthesised several essential vitamins, such as vitamin B1, C, D, and A. Each of these represented another part of the nutrient puzzle.

But it’s thanks to the creative, yet logical visions of several scientists that we now have robust dietary guidelines, foods fortified with vitamins, vitamin supplements, and a complete understanding of the importance of vitamins in human nutrition and of vitamin-deficiency related diseases.

References

Semba, R. D., 2012. The discovery of the vitamins. Int. J. Vitam. Nutr. Res, 82(5), 310-315.

Badii, C., Solan, M., and Reed-guy, L., 2017. Beriberi. Retrieved from https://www.healthline.com/health/beriberi#causes.