| Table of contents |
|
2 Vitamin deficiency diseases 3 Is vitamin D a real vitamin? 4 Vitamins A and K 5 Names 6 Whatever Happened to Vitamin F? 7 Non-human vitamins |
Vitamins were first recognised by the diseases that occur from a lack of certain foods; for example, the British Royal Navy recognised that a constituent of limes prevented scurvy (one result of not having enough vitamin C over an extended period of time), so limes were added to the diet of sailors. Vitamin D prevents rickets, and so forth.
Vitamins can be divided in two groups by their solubility in water:
Water-soluble vitamins
Introduction
Fat-soluble vitamins
Fat-soluble vitamins may be stored in the body and can cause toxicity when taken in excess; water-soluble vitamins are not stored in the body. Unlike food, water, and – for aerobic organisms – air, an organism can survive for some time without vitamins, although prolonged vitamin deficit results in a disease state.
| Deficient vitamin | Disease |
|---|---|
| A | night blindness |
| B1 | beriberi |
| B2 | ariboflavinosis |
| B12 | pernicious anaemia |
| niacin | pellagra |
| C | scurvy |
| D | rickets |
Other vitamin deficiencies are simply called after the name of the vitamin, like vitamin K deficiency disease.
On the other hand, vitamins D and E are still usually called by their symbolic names,
and A and K don't even have proper chemical names (since they are mixtures of chemicals).
The names ascorbic acid and vitamin C are used with similar frequency.
Different organisms need different trace organic substances. The list of vitamins in this article refers to humans. Most mammals need, with few exceptions, the same vitamins (except that most species don't need ascorbic acid). The further we go from mammals, the more diverse organisms' requirements become. For example, some bacteria need adenine.
See pharmacology.
External links:
Is vitamin D a real vitamin?
Vitamin D is synthetized by human body, but in quantities that are not always sufficient. The level of synthesis depends on exposure to sunlight, so in winter and in polar areas it acts more like a vitamin, and in summer and in equatorial areas it acts less like a vitamin.
So it's usually treated as a vitamin, but one that isn't required in some areas and seasons.Vitamins A and K
Neither vitamin A nor vitamin K is a single chemical substance,
but all derivatives fulfill the same functions in organisms (or are converted into the active form by the organism), so taking just one of the derivatives is sufficient for good health. The derivatives differ in chemical structure and level of activity.Names
Some obsolete vitamin names:
The usage of names in the format "vitamin letter" and "vitamin letter number" is diminishing.
This is especially true for vitamins H, M, B1, B2, B3, and B5, which are usually called by their proper chemical names.Whatever Happened to Vitamin F?
Vitamin F was the designation originally given to essential fatty acids that the body cannot manufacture. They were "de-vitaminized" because they are fatty acids. Fatty acids are a major component of fats. Non-human vitamins