What are international units?
International units is an internationally recognized measure defined by the international conference for the unification of formulas based on the reference preparation of the substance provided by the World Health Organization (WHO) by the expert committee for biological standardization. It is most commonly considered to be a degree of fat -soluble vitamins in food packaging and refilling, but is also applied to biological substances such as vaccines, enzymes and hormones. The WHO sample is used to assess other substances to ensure consistency and serve as a standard for determining doses.
The abbreviation for the international unit is I.U. International units differ from standard units of other types such as kilograms, pounds, liters or liters. Working with these other types of measurements would be expected, say, a cup of one item and a cup of other items that are the same amount. However, international units refer to biological activity, which is the result of the administration of the substance.
as a result may be 2 mezal units of one substance by another amount of this substance than 2 international units of another substance. In fact, this difference is more likely than not and there is no measurement of IU into milligrams or other weights. In addition, 2 IU vaccines from a particular manufacturer may have a mass other than 2 IUs from another manufacturer, for example, there could be other ingredients that do not take into account in biological efficiency.
USP - United States Pharmacopeia unit - is similar and expresses drug efficiency rather than their quantity. USP units are usually identical to international units. The shortage of such a units on many natural supplements is one of the factors that leads to warnings that doses may not be equivalent to different BA.
Some substances that were once determined by IU measurements have now undergone a more thorough chemical analysis that allowed better to understandthe art of their qualities. In such cases, it was possible to replace the measure of the biological efficiency of the weight or both can be used. For example, before simply specifying IU, the US Medical Institute of the National Academy of Sciences recommends 5 micrograms or 200 IU vitamin D for all under 50 years.