Vitamin A is a vitamin that is essential for gene transcription, and maintain healthy skin and vision. Vitamin A is found in two main forms, retinol and carotene. Retinol is a vitamin A preformed which can be found in animal food sources. Our bodies can convert plant carotenoids such as alpha carotene, beta-carotene and gamma-carotene can be found in fruits and vegetables into vitamin A. So, carotenoids are called provitamin A. Eggs, milk, carrots, broccoli, pumpkin, beef liver, sweet potatoes and spinach are some of vitamin A foods. this vitamin is stored in fat tissue and liver in the body. Vitamin A serves for several purposes in the human body.
Vitamin A toxicity
Excessive intake of vitamin A should be avoided, because an overdose of this vitamin can cause some side effects. Basically, this vitamin is stored in fat tissue and liver, to be used by the body. So, too much or vitamin A toxicity can accumulate in the liver, which in turn, can cause a number of health complications. Typically, the presence of vitamin A in the body overload can cause nausea, vomiting, irritability, dry skin and nails, fatigue, hair loss, muscle pain, weight loss, headache, menstrual problems, fatigue, bleeding gums, jaundice, pain stomach, blurred vision and fractures. In extreme cases, can lead to an enlarged liver and spleen.
Acute toxicity
Arctic explorer experience drowsiness, irritability, headache and vomiting within a few hours after eating polar bear liver or liver seals, which contains a lot of vitamin A. Vitamin A tablets that contain 20 times the recommended daily dose, which is used for the prevention and relieve skin disease, sometimes cause similar symptoms, even if taken as directed.
Chronic toxicity
Chronic poisoning in children and adults greater is usually the result of consuming large doses of vitamin A (10 times the recommended daily dose) for months. Vitamin A toxicity can occur in a baby in a few weeks.
The initial symptoms of chronic toxicity are:
- Blond hair and rough
- Loss on the part of eyelashes
- Lips are chapped
- Skin dry and rough.
Severe headaches, increased pressure in the brain and general weakness ensues. The growth of bone and joint pain are common, especially in children. Liver and spleen may be enlarged. Babies born to mothers who took isotretinoin (an artificial vitamin A used to treat a skin disorder) during pregnancy may have birth defects.
Vitamin A toxicity diagnosis is made based on symptoms and high levels of vitamin A in the blood. Symptoms will disappear within 4 weeks after the halt to the use of vitamin A supplementary. Beta-carotene is found in vegetables such as carrots, gradually transformed by the body into vitamin A and can be consumed in large quantities without causing toxicity. Although the skin will change to amber (carotenosis), especially the skin on the palms and soles of the feet, but does not cause other side effects.
It can be concluded that, when consumed with the right dose and with proper care, this vitamin can be really effective to improve general health. Because it is a fat-soluble vitamin, the excess amount can not be excreted through the urine. Excessive vitamin A tend to accumulate in the liver and fat tissue, and thus produce the side effects mentioned above or symptoms of poisoning. So it is very important to take vitamin A only in the required amount. People taking supplements should be careful to not take vitamin A which is higher than the recommended dose. Vitamin A toxicity occurs mainly with preformed vitamin A, and not the form of carotenoids. However, an excess of carotenoids may cause carotenodermia, a condition characterized by discoloration of yellow or yellow-orange skin.
