Vitamin poisoning
Encyclopedia
Vitamin poisoning, hypervitaminosis or vitamin overdose
Drug overdose
The term drug overdose describes the ingestion or application of a drug or other substance in quantities greater than are recommended or generally practiced...

refers to a condition of high storage levels of vitamin
Vitamin
A vitamin is an organic compound required as a nutrient in tiny amounts by an organism. In other words, an organic chemical compound is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on...

s, which can lead to toxic
Toxicity
Toxicity is the degree to which a substance can damage a living or non-living organisms. Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell or an organ , such as the liver...

 symptom
Symptom
A symptom is a departure from normal function or feeling which is noticed by a patient, indicating the presence of disease or abnormality...

s. The medical names of the different conditions are derived from the vitamin involved: an excess of vitamin A, for example, is called hypervitaminosis A
Hypervitaminosis A
Hypervitaminosis A refers to the effects of excessive vitamin A intake.-Presentation:Effects include* Birth defects* Liver problems* Reduced bone mineral density that may result in osteoporosis* Coarse bone growths...

.

Generally, toxic levels of vitamins are achieved through high supplement intake and not from dietary sources. Toxicities of fat-soluble vitamins result also can be caused by a large intake of highly fortified
Food fortification
Food fortification or enrichment is the process of adding micronutrients to food. It can be purely a commercial choice to provide extra nutrients in a food, or sometimes it is a public health policy which aims to reduce numbers of people with dietary deficiencies in a population.Diets that lack...

 foods, but foods rarely deliver dangerous levels of fat-soluble vitamins.

The Dietary Reference Intake
Dietary Reference Intake
The Dietary Reference Intake is a system of nutrition recommendations from the Institute of Medicine of the U.S. National Academy of Sciences. The DRI system is used by both the United States and Canada and is intended for the general public and health professionals...

 recommendations from the United States Department of Agriculture
United States Department of Agriculture
The United States Department of Agriculture is the United States federal executive department responsible for developing and executing U.S. federal government policy on farming, agriculture, and food...

 define a "tolerable upper intake level" for most vitamins.

High dosage vitamin A
Vitamin A
Vitamin A is a vitamin that is needed by the retina of the eye in the form of a specific metabolite, the light-absorbing molecule retinal, that is necessary for both low-light and color vision...

; high dosage, slow release vitamin B3; and very high dosage vitamin B6
Vitamin B6
Vitamin B6 is a water-soluble vitamin and is part of the vitamin B complex group. Several forms of the vitamin are known, but pyridoxal phosphate is the active form and is a cofactor in many reactions of amino acid metabolism, including transamination, deamination, and decarboxylation...

 alone (i.e. without vitamin B complex) are sometimes associated with vitamin side effects that usually rapidly cease with supplement reduction or cessation.

Fat soluble

With few exceptions, like some vitamins from B complex, hypervitaminosis usually occurs more with fat-soluble vitamins, which are stored 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.

Conditions include:
  • Hypervitaminosis A
    Hypervitaminosis A
    Hypervitaminosis A refers to the effects of excessive vitamin A intake.-Presentation:Effects include* Birth defects* Liver problems* Reduced bone mineral density that may result in osteoporosis* Coarse bone growths...

  • Hypervitaminosis D
    Hypervitaminosis D
    Hypervitaminosis D is a state of vitamin D toxicity.The recommended daily allowance is 400 IU per day. Overdose has been observed at 1925 µg/d...

  • Hypervitaminosis E
    Hypervitaminosis E
    Hypervitaminosis E is a state of vitamin E toxicity.Because vitamin E can act as an anticoagulant and may increase the risk of bleeding problems, many agencies have set an upper tolerable intake level for vitamin E at 1,000 mg per day. This UL was established due to an increased incidence of...

  • Hypervitaminosis K

Water soluble

Vitamin C
Vitamin C
Vitamin C or L-ascorbic acid or L-ascorbate is an essential nutrient for humans and certain other animal species. In living organisms ascorbate acts as an antioxidant by protecting the body against oxidative stress...

 has a brief, pronounced laxative
Laxative
Laxatives are foods, compounds, or drugs taken to induce bowel movements or to loosen the stool, most often taken to treat constipation. Certain stimulant, lubricant, and saline laxatives are used to evacuate the colon for rectal and/or bowel examinations, and may be supplemented by enemas under...

 effect when taken in large amounts. This effect can be lessened by taking the large amount 5-10 grams per day
Vitamin C megadosage
Vitamin C megadosage is the consumption of vitamin C in doses comparable to the amounts produced by the livers of most other mammals and well beyond the current Dietary Reference Intake...

 in divided (smaller) doses.

Vitamin B6 excess
Vitamin B6 excess
Vitamin B6 excess may present with a subepidermal vesicular dermatosis and sensory peripheral neuropathy....

 can be mitigated by taking a low-dose B6 supplement together with a B-complex (which normally also contains B6), or with food rich in B vitamins, e.g., cereals.

Minerals

High doses of mineral supplements can also lead to side effects and toxicity. Mineral-supplement poisoning does occur occasionally, most often due to excessive intake of iron-containing supplements.

Comparative safety statistics

Death
Death
Death is the permanent termination of the biological functions that sustain a living organism. Phenomena which commonly bring about death include old age, predation, malnutrition, disease, and accidents or trauma resulting in terminal injury....

 by vitamin poisoning appears to be quite uncommon in the US, typically none in a given year. For example, in the United States, overdose exposure to all formulations of "vitamins" was reported by 62,562 individuals in 2004 (nearly 80%(~78%, n=48,989) of these exposures were in children under the age of 6), leading to 53 "major" life-threatening outcomes and 3 deaths(2 from Vitamins - D and E; 1 from polyvitaminic type formula, with iron and no fluoride). This may be compared to the 19,250 people who died of unintentional poisoning of all kinds in the U.S. in the same year (2004). In 2007, 58,000 exposures to various vitamins and multivitamin-mineral formulations were reported to poison control centers, which resulted in 17 severe reactions and 1 death. In 2008 there were no deaths reported from vitamin overdose, as has been the case for 17 of the last 25 reporting-years.

Before 1998, several deaths per year were associated with pharmaceutical iron-containing supplements, especially brightly-colored, sugar
Sugar
Sugar is a class of edible crystalline carbohydrates, mainly sucrose, lactose, and fructose, characterized by a sweet flavor.Sucrose in its refined form primarily comes from sugar cane and sugar beet...

-coated, high-potency iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

 supplements, and most deaths were child
Child
Biologically, a child is generally a human between the stages of birth and puberty. Some vernacular definitions of a child include the fetus, as being an unborn child. The legal definition of "child" generally refers to a minor, otherwise known as a person younger than the age of majority...

ren. Unit packaging restrictions on supplements with more than 30 mg of iron have since reduced deaths to 0 or 1 per year. These statistics compare with 59 confirmed deaths due to aspirin
Aspirin
Aspirin , also known as acetylsalicylic acid , is a salicylate drug, often used as an analgesic to relieve minor aches and pains, as an antipyretic to reduce fever, and as an anti-inflammatory medication. It was discovered by Arthur Eichengrun, a chemist with the German company Bayer...

 poisoning in 2003 and 147 deaths known to be associated with acetaminophen-containing products in 2003.
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