谁知道关于维生素的事?
包括维生素的英文怎么拼?含不含钙等元素?
最好全英文,附中文.
参考答案:Vitamin
Vitamins are nutrients required in large amounts (most vitamins) for essential metabolic reactions in the body and to improve health immensly. The term vitamin does not encompass other essential nutrients such as dietary (trace)minerals, essential fatty acids, or essential amino acids. Nor does the term refer to the large number of other nutrients that promote health, but are not (taught to be) strictly essential.
Vitamins act both as catalysts and substrates in chemical reactions. When acting as a catalyst, vitamins are bound to enzymes and are called cofactors, for example vitamin K forms part of the proteases involved in blood clotting. Vitamins also act as coenzymes to carry chemical groups between enzymes, for example folic acid carries various forms of carbon groups (methyl, formyl or methylene) in the cell.
Until the 1900's, vitamins were obtained solely through food intake. Many food sources contain different ratios of vitamins. Therefore, if the only source of vitamins is food, a seasonal, yearly or even daily change in diet also alters the ratio of ingested vitamins. Many vitamins can be stored by the body over a range of dosages and short term deficiencies (e.g. during a particular food growing season), do not always result in disease.
Vitamins have been produced as commodity chemicals and made widely available as inexpensive pills for several decades allowing for consistent supplementation to dietary intake.
参考资料：