Hypervitaminosis – Excessive Vitamins
Excessive intake of vitamins, known as hypervitaminosis, is a severe disorder that occurs when there is an excess of vitamins accumulated in the body due to improper or uncontrolled intake.
Vitamins are divided into water-soluble (B-group vitamins and vitamin C) and fat-soluble (A, D, E, and K) vitamins. Fat-soluble vitamins accumulate more rapidly, so exposure to an excess of them is considered more toxic.
Hypervitaminosis rarely occurs significantly, and it is more commonly associated with vitamins A and D. Excesses in vitamins E and C also occur rarely, along with some B-group vitamins.
Excessive intake of vitamins can occur at any age and is usually due to the following:
- Taking high doses of vitamin supplements for a prolonged period.
- Improper use of supplements.
- Self-administration of dietary supplements without monitoring.
- Excessive consumption of liver, kidney, and fish oils (rarely causing vitamin A excess).
Symptoms of vitamin excess can be categorized as follows:
- General symptoms: weakness, increased fatigue.
- Blood disorders: bleeding may occur in cases of excess vitamin E, but this is rare.
- Gastrointestinal symptoms: nausea, vomiting, diarrhea, abdominal pain, bloating, liver and spleen enlargement (rarely).
- Neurological symptoms: headache, dizziness, peripheral neuropathy, increased irritability, and in severe cases, consciousness disorders.
- Dermatological and skin appendage symptoms: dry skin and mucous membranes, cheilosis, dermatitis, eyebrow loss, desquamation of the skin.
- Bone-related symptoms: disturbances in bone density and susceptibility to fractures.
The effects of excessive vitamin intake, known as hypervitaminosis, vary depending on the type of vitamin. Here are some important points for each type:
Vitamin D:
- Plays a role in bone formation and supports the immune and hormonal systems.
- Excessive doses lead to increased blood calcium levels, bone destruction, and increased risk of fractures.
Vitamin A (retinol):
- Essential for cellular structure functions, formation of visual pigments, and tissue strength.
- Excessive doses may lead to toxic effects, including skin, nervous system, and bone tissue disorders.
Vitamin E (tocopherol):
- It has antioxidant effects and protects cell membranes from oxidation.
- Excessive doses may cause rare blood platelet disorders and increased bleeding.
Vitamin K:
- Regulates blood clotting and is used for prevention and treatment of bleeding.
- There is no clear evidence of toxicity when consumed from natural sources, but there are reports of hypervitaminosis cases with the use of synthetic supplements.
It is important to achieve a balance in vitamin intake and avoid excess to prevent potential negative effects on health.
Water-soluble Vitamins:
The kidneys quickly excrete water-soluble vitamins from the body, so hypervitaminosis in this case is rare. Individuals easily tolerate high doses of these elements, and toxic effects only appear when vitamin C, B3, and B6 levels exceed the daily limit by tens of times, usually due to the consumption of dietary supplements.
Vitamin B-containing foods include grains, especially non-fortified ones, animal products, vegetables, and fruits. Vitamins also play a role in energy metabolism, protein, fat, and carbohydrate exchange, and are also important for the nervous system.
When regularly consuming a varied diet, individuals obtain sufficient amounts of these vitamins. The normal concentration of vitamin B6 in the blood exceeds 30 nanomoles per liter or 7.4 nanograms per milliliter.
Vitamin C is essential for collagen synthesis, hormones, amino acids, and carnitine, which promote muscle energy and fat burning. The vitamin also affects wound healing, iron absorption, bone health, and helps boost immunity.
Citrus fruits alone are not rich in vitamin C. Kiwi, sweet pepper, cress, cherries, and broccoli are also among the highest sources.
Children’s requirements range from 15 to 45 milligrams per day, while adults’ requirements range from 75 to 90 milligrams per day. The maximum allowed limit is 2,000 milligrams per day.
Classification and Stages of Vitamin Excess:
Hypervitaminosis can be classified into six types, including:
- Vitamin D Hypervitaminosis;
- Vitamin A Hypervitaminosis (acute and chronic);
- Vitamin E Hypervitaminosis;
- Vitamin K Hypervitaminosis (previously seen in the context of drug therapy);
- Vitamin B Hypervitaminosis (B3 and B6);
- Vitamin C Hypervitaminosis.