The discovery of vitamins came about much later than that of the major food types, largely because they are often required in such tiny amounts that they are difficult to detect. The first vitamin isolated in a concentrate was thiamine, extracted from rice husks in 1912 by Casimir Funk, a polish biochemist. He used this to alleviate the symptoms of beri beri, a disease found in Japanese sailors who lived on little else but white (unhusked) rice. It was Casimir Funk who coined the name ‘vitamine’ meaning vital amine. The ‘e’ was later dropped.
In the same year, the English biochemist Frederick Gowland Hopkins (shown below), demonstrated that a diet of pure protein, carbohydrate, fat, water and minerals could not sustain life in rats, but that the addition of unprocessed foods such as milk restored health. Clearly there must therefore be some other substance present, which food refinement removes.
Evidence for the presence of more than one vitamin came from the American E.V McCollum, who showed that young rats require both water soluble and fat soluble vitamins (hence the modern day grouping).
Much of the research into discovering new vitamins centred not on precise structures and formulas (this would have been hard until relatively recently), but on non-pathological diseases which could be cured by the addition of a particular food into the diet of the patient. Such treatments had been carried out long before vitamins were actually discovered and named. Goose liver, (now known as a source of vitamin A) was used in ancient Greece, Rome and Arabia, as a cure for night-blindness. Perhaps the most famous use of a foodstuff to treat a disease was by James Lind, a Scottish doctor in the Navy, who discovered in 1757 that citrus fruits could be added to the diet of long-distance sailors to prevent the onset of scurvy. This led to the compulsory inclusion of limes in the diets of British sailors, and the resulting nickname: ‘Limeys’. Scurvy was later found to be a disease resulting from a vitamin C deficiency.