Diseases were initially associated with deficiency of the Vitamin B complex and other vitamins such as Vitamin A, and C and such diseases took a human toll. The discovery, therefore, was a move in the right direction.
Christiaan Eijkman, a Dutch Physician while investigating beriberi, a condition that is characterized by weight loss, weakness, confusion, and occasionally death, started the journey towards the discovery of the vitamin B complex. Later on, Frederick Godland, an English biochemist, linked beriberi and scurvy to nutrition.
It is in 1926 that Willem Donath and Barend Jansen isolated the anti-beriberi factor that would later be named B1, otherwise known as thiamine. Earlier, Theodor Wagner and Richard Kuhn had identified B2 otherwise known as riboflavin. Vitamin B6 was discovered in 1934 by Gyorgy and his colleagues while vitamin B12 was discovered by Karl Folkers. Folkers also participated in the isolation and synthesis of B1 and B6.
In the initial stages, deficiency of these vitamins was associated with disease states such as beriberi, pellagra, and megaloblastic anemia among others; it is in the understanding that a certain level of the vitamins was considered normal, high, or low. Globally speaking, the listed conditions are largely a presentation of the symptoms of the respective deficiency in the vitamins.
It happened that healthy individuals had their B vitamin levels within a certain range and had the levels regulated within that level. Any deviation either below the lower limit or above the upper limit led to a disease state. From here, a normal range was described and that could be used as a reference. From this range, either high or low blood B vitamin levels would be described.
In conclusion, the discovery of vitamins and the association of their deficiency to disease states has helped those in the medical profession to have a deeper understanding of these conditions. Additionally, initiatives can now be implemented aimed at reducing vitamin B deficiencies.