Excessive intake of vitamin supplements carries the risk of serious diseases. Which vitamins can be overdosed? What are the symptoms of a vitamin overdose?

Both a complete vitamin deficiency (avitaminosis) or a partial (hypovitaminosis) as well as their excess (hypervitaminosis) are detrimental to the body and may lead to certain diseases.Hypervitaminosismainly concerns fat-soluble vitamins (A, D, E and K), which are accumulated in adipose tissue rather than dissolved in water and excreted with urine. Hypervitaminosis not caused by artificial supplementation may occur in people who eat a poorly varied diet and eat the same products for a long time. In other cases, this disease affects mainly those who take several vitamin supplements at the same time without prior medical consultation. In addition, the coexistence of certain diseases may reduce the toxicity threshold of fat-soluble vitamins, and then taking even small daily doses may cause symptoms of hypervitaminosis.Overdoseindividualvitaminssynthetic no poses the same risk - some of them are of low toxicity. An example is vitamin E (in other words - tocopherol) in its natural form, occurring, among others, in almonds, nuts, oils. In her case, even several dozen times the recommended daily dose usually does not cause symptoms of poisoning, which may include: general fatigue, muscle weakness, headaches and visual disturbances. However, taking too high doses of tocopherol during pregnancy may have an adverse effect on the fetus - although it has not been scientifically proven (so far only animal studies have been conducted).

Vitamin C - ascorbic acid

In particularly sensitive people, an overdose of vitamin C (so-called ascorbic acid), contained mainly in fruits and vegetables, may cause urate and oxalate crystallization in the kidneys and the formation of kidney stones, and taking very high doses may lead to disorders in the work of the digestive and nervous systems. In addition, hypervitaminosis associated with the consumption of excess vitamin C is associated with the occurrence of skin rashes, and its long-term use can be addictive!

Vitamin K

Vitamin K is found in broccoli, spinach, lettuce, dairy products and eggs, but it can also be synthesized by intestinal bacteria and regenerated in the liver. Supplementation with vitamin K is primarily required by children whose digestive system (and with it the possibility of efficient synthesis of this compound) is not yet properly developed, and people who have received antibiotic therapy that destroys the natural intestinal bacterial flora. An overdose of vitamin K, which regulates blood clotting, leads to the breakdown of red blood cells and thus anemia. The effects of an excess of this compound are also sweating and a constant feeling of heat, and in infants - jaundice, and even damage to the brain tissue!

Vitamin D - calciferol

Vitamin D plays an important role in the regulation of calcium-phosphate metabolism and in stabilizing the proper structure of the skeleton. It is synthesized from a precursor supplied in the diet (sea fish and fish oil) in the liver and kidneys and in skin cells under the influence of sunlight, so the amount of naturally produced vitamin D is subject to seasonal fluctuations. Older people are at risk of deficiency, as the ability to synthesize it decreases with age. The natural mechanism of vitamin D storage in the body can lead to toxic levels and hypercalcemia (increased levels of calcium in the blood) causing calcification of the heart, kidneys, lungs and blood vessels. Hypervitaminosis is manifested by weakness, drowsiness, depression, headaches and abdominal pain, decreased appetite, diarrhea or constipation, vomiting, kidney stones, polyuria. Hypervitaminosis D is possible only with synthetic vitamin supplementation, which means that there is no risk of intoxication during excessive sun exposure or a diet rich in fish. The exception are children with rickets - in them the symptoms of hypervitaminosis are sometimes the result of excessive exposure to sunlight - then there is an increased uptake of calcium by the bones at the expense of lowering the level of its ions in the serum, and the resulting hypocalcemia may result in the development of tetany.

Vitamin B group

When taken orally, it is difficult to overdose vitamin B1 (thiamine contained in the liver, eggs, legumes) and vitamin B2 (riboflavin), which are abundant in liver, fish and dairy products, because their poor solubility in the intestines protects the body from absorption too much of these compounds, and their excess is excreted in the urine. Possibility of overdose (manifested by general weakness, edema, nausea and vomiting, muscle tremors, arrhythmias,occurrence of an allergic reaction) occurs when given by injection.

  • vitamin B3 (niacin also called vitamin PP) is contained in the liver. Overdose causes dermatological symptoms (rash, itching and reddening of the skin), increased blood glucose, cardiac arrhythmia, loss of appetite; taking very high doses of vitamin B3 may lead to changes in the macula and the retina of the eye, and to a gradual deterioration or even loss of vision. Presumably, excess niacin may also have a negative effect on the developing fetus
  • Pantothenic acid, i.e. vitamin B5 necessary, among others for the proper course of the transformation of proteins, fats and carbohydrates, the synthesis of some hormones, it is a compound that occurs commonly in nature (the name "pantothenic" means "ubiquitous"). The toxic effect of the excess of this vitamin on the body has not been proven, but a significant excess of the recommended daily doses may result in digestive system ailments and diarrhea
  • Excess vitamin B6 (pyridoxine), the richest source of which are fish, meat, potatoes, causes difficulties in movement, impaired coordination of movements, numbness of the limbs. In very sensitive people, the symptoms of hypervitaminosis may appear after taking about 50 mg of pyridoxine (the daily requirement for an adult is 1-2 mg)
  • Vitamin B9, or folic acid, found in green leafy vegetables, has a positive effect on the nervous system. Overdose causes insomnia, irritability and depression, gastrointestinal disturbances, or allergic skin reactions. Vitamin B12, responsible for the regulation of red blood cell formation, when taken in too high doses is not toxic, but its excess may cause allergic symptoms in sensitive people, and with significantly exceeded doses - nose bleeds.

Vitamin A - retinol

A rich source of vitamin A is the liver of animals, and provitamins A - carrots, broccoli, spinach. Most retinol overdoses may be due to excessive fish oil consumption. Regular intake of retinol in a tenfold increase in the recommended dose may lead to acute or chronic poisoning, the symptoms of which are headaches, irritability, heaviness, diarrhea, bone decalcification, kidney disorders, skin reactions, hair loss and malaise. Supplementation with this vitamin in pregnant women should be properly balanced, because in the event of an overdose, fetal development disorders may occur; for this reason, expectant mothers should avoid large amounts of liver. The safest formprophylactic supplementation with vitamin A is taking its precursor - beta-carotene, because only as much of the precursor as the current demand for this ingredient is transformed in the body into retinol.

Vitamin overdose can be dangerous

Source: Lifestyle.newseria.pl

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