Can I Overdose On Vitamins?

Ingesting too much vitamin A can lead to birth defects, liver abnormalities, central nervous system disorders, and reduced bone density, according to the National Institutes of Health. While it's natural to think of vitamins as healthy, it can be more dangerous to consume too much than too little of certain vitamins. It's important to know which vitamins can be dangerous and to recognize the warning signs of overdose.

Types

Vitamin C and B-complex vitamins are water-soluble vitamins that your body cannot store in fatty tissue. Instead, your body quickly excretes any excess water-soluble vitamins. This means that while you must consume these vitamins daily to maintain adequate levels, it is very difficult to overdose on them, although it is never advisable to take megadoses of water-soluble vitamins.

Your body stores surplus fat-soluble vitamins in fatty tissue. Fat-soluble vitamins include vitamins A, D, E and K. Because your body keeps excess fat-soluble vitamins instead of excreting them, it's possible for these vitamins to build up to dangerous levels in the body, a condition known as hypervitaminosis.

Time Frame

Chronic hypervitaminosis occurs when you consume too much of a fat-soluble vitamin over time, allowing it to slowly build up in your body. Exactly how long it takes for chronic hypervitaminosis to develop depends on the vitamin and the size of the daily dose. A single very large dose of a fat-soluble vitamin can trigger acute hypervitaminosis.

Symptoms

Symptoms of vitamin A overdose vary from mild, blurred vision or dizziness, to severe, softening of the cranium and liver damage. Hypervitaminosis D is generally less dangerous, but can lead to constipation, anorexia, irritability, and vomiting. Vitamin E overdoses are extremely uncommon, but the MayoClinic.com links high-dose vitamin E to possible increased risk of bleeding. High doses of vitamin K are not known to cause hypervitaminosis.

Treatment

Fortunately, most symptoms of vitamin overdoses are reversible. Treatment is usually limited to alleviating any symptoms and reducing the intake of the vitamin. In rare cases fat-soluble vitamin overdoses can result in permanent organ and bone damage or in birth defects in the children of women who overconsumed vitamins during pregnancy.

Prevention

The recommended dosage of water-soluble and fat-soluble vitamins depends on age and gender. Specific conditions such as pregnancy or lactation can also influence dosing recommendations. It's very difficult to consume enough vitamins in your normal diet to trigger hypervitaminosis. Oversupplementation causes most overdoses. Consult a physician before taking supplemental vitamins.