Science · Medicine & the body

Vitamins

Named 1912

Medicine — nutrition and the deficiency diseases

Organic compounds that the body needs in tiny quantities but cannot make for itself in sufficient amounts, so they must come from the diet. Thirteen are recognised for humans: A, C, D, E, K and the eight of the B group. Four — A, D, E and K — are fat-soluble and can be stored, and in excess can poison; the rest are water-soluble and largely excreted. Their existence was deduced backwards from the diseases caused by their absence: scurvy, beriberi, pellagra, rickets and pernicious anaemia. Casimir Funk named them "vitamines" in 1912, and the final "e" was dropped in 1920 when it turned out that not all of them are amines.

How to spot them

▸Thirteen in all: A, C, D, E, K and eight B vitamins
▸Fat-soluble A, D, E and K are stored; water-soluble C and the B group are not
▸Each is tied to a deficiency disease: C to scurvy, B1 to beriberi, B3 to pellagra, D to rickets, B12 to pernicious anaemia
▸Funk coined the name in 1912; the 'e' was dropped in 1920
▸The B numbering has gaps, because several supposed members turned out not to qualify

Key facts

Casimir Funk's coinage of 1912, which lost its final letter in 1920 (1912)

'Vitamine', from vital amine; Jack Drummond proposed the shortened spelling

James Lind's trial aboard HMS Salisbury in 1747, and the fruit that gave British sailors a nickname (1747)

One of the first controlled clinical trials; citrus, and hence 'limeys'

Christiaan Eijkman's chickens fed on polished rice in Java, and the disease they developed (1897)

Beriberi and thiamine; Eijkman shared the 1929 Nobel Prize

Joseph Goldberger's four Ds: dermatitis, diarrhoea, dementia and death

Pellagra in the American South, caused by a maize diet short of niacin

Frederick Gowland Hopkins's 'accessory food factors', honoured in 1929 (1929)

His feeding experiments showed that purified diets are not enough

Albert Szent-Györgyi isolating hexuronic acid from Hungarian paprika (1932)

Ascorbic acid; he won the 1937 Nobel Prize in Physiology or Medicine

Henrik Dam's chosen letter, from the Scandinavian and German for coagulation (1943)

Vitamin K; Dam shared the 1943 Nobel Prize with Edward Doisy

Minot, Murphy and Whipple curing pernicious anaemia by feeding patients raw liver (1934)

The cobalt-containing factor later identified as B12

Key ideas

The concept was arrived at by subtraction: diets containing ample protein, fat, carbohydrate and minerals still killed people, so something else in small quantity had to be essential.
One of them is not really a vitamin at all. Vitamin D is synthesised in the skin from a cholesterol derivative under ultraviolet light and acts on distant tissues, which makes it a hormone.
Most mammals manufacture their own vitamin C; humans, the other primates, guinea pigs and a few other species have lost the final enzyme in the pathway, which is why scurvy is a human problem.

Quick-fire facts

•Thirteen are recognised: A (retinol), C (ascorbic acid), D (calciferol), E (tocopherol), K, and B1 thiamine, B2 riboflavin, B3 niacin, B5 pantothenic acid, B6 pyridoxine, B7 biotin, B9 folate and B12 cobalamin
•A, D, E and K are fat-soluble; excess A and D can be toxic
•Casimir Funk coined 'vitamine' in 1912; Jack Drummond proposed dropping the 'e' in 1920
•James Lind ran his citrus trial aboard HMS Salisbury in 1747 and published 'A Treatise of the Scurvy' in 1753; the Royal Navy adopted lemon juice in 1795
•Christiaan Eijkman and Frederick Gowland Hopkins shared the 1929 Nobel Prize in Physiology or Medicine for the antineuritic vitamin and the growth-stimulating vitamins
•Beriberi is thiamine deficiency; wet beriberi affects the heart, dry beriberi the nerves
•Pellagra is niacin deficiency, characterised by the four Ds; Joseph Goldberger proved its dietary cause in the 1910s
•Rickets in children and osteomalacia in adults follow vitamin D deficiency; Edward Mellanby demonstrated the cure with cod liver oil
•Vitamin B12 contains cobalt; Dorothy Hodgkin solved its structure, work cited in her 1964 Nobel Prize in Chemistry
•Henrik Dam named vitamin K for 'Koagulation'; he and Edward Doisy shared the 1943 Nobel Prize
•Albert Szent-Györgyi won the 1937 Nobel Prize in Physiology or Medicine for vitamin C, and Walter Haworth the Chemistry prize the same year for its structure and synthesis
•Vitamin A deficiency causes night blindness and xerophthalmia, the commonest preventable cause of childhood blindness worldwide
•Linus Pauling was a prominent and much-criticised advocate of megadoses of vitamin C

Drill it — 10 cards

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Sources

NHS — Vitamins and minerals
The Nobel Foundation — The Nobel Prize in Physiology or Medicine 1929