Hypervitaminosis is a condition of abnormally high storage levels of vitamins, which can lead to various symptoms as over excitement, irritability, or even toxicity. Specific medical names of the different conditions are derived from the given vitamin involved: an excess of vitamin A, for example, is called hypervitaminosis A. Hypervitaminoses are primarily caused by fat-soluble vitamins  (D and A), as these are stored by the body for longer than the water-soluble vitamins.Generally, toxic levels of vitamins stem from high supplement intake and not always from natural sources but rather the mix of natural, derived vitamins and enhancers (vitamin boosters). Toxicities of fat-soluble vitamins can also be caused by a large intake of highly fortified foods, but natural food in modest levels rarely deliver extreme or dangerous levels of fat-soluble vitamins. The Dietary Reference Intake recommendations from the United States Department of Agriculture define a "tolerable upper intake level" for most vitamins. For those who are entirely healthy and do not experience long periods of avitaminosis, vitamin overdose can be avoided by not taking more than the normal or recommended amount of multi-vitamin supplement shown on the bottle and not ingesting multiple vitamin-containing supplements concurrently. Signs and symptoms
A few described symptoms:

Causes
With few exceptions, like some vitamins from B-complex, hypervitaminosis usually occurs with the fat-soluble vitamins A and D, which are stored, respectively, in the liver and fatty tissues of the body. These vitamins build up and remain for a longer time in the body than water-soluble vitamins.
Prognosis
The condition is usually self-limiting, and thus not indicated for surgery. Terminology
The term has several meanings on histological and symptomatic levels and on both levels usage overlaps with mastalgia, fibrocystic disease and specific sub- or superclasses of nonpuerperal mastitis. While this is not ideal for a definition it results from actual usage in international literature. Because research literature regarding duct ectasia is anything but abundant it is probably easiest to determine the exact meaning(s) intended by the respective authors on a case-by-case basis and this section can offer only a few hints. Typical usage in North America is a synonym of nonpuerperal mastitis, including the special cases of granulomatous mastitis, comedo mastitis, subareolar abscess with or without squamous metaplasia of lactiferous ducts and fistulation.Simple duct widening should be carefully distinguished from more complex histological changes. References


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