Vitamin A Deficiency and Excess

DEFINITIONS

Vitamin A (retinol) mainly found in fish oils, liver, egg yolks, butter and cream.
Green leafy vegetables and yellow vegetables contain carotenoids (eg beta-carotene), which gradually be changed by the body into vitamin A.

Sources of vitamin A

Most of the vitamin A stored in the liver.
One form of vitamin A (retinal) is a component of the photoreceptors (nerve cells that are sensitive to light) in the retina of the eye.
Other forms of vitamin A (retinoat acid) play a role in maintaining healthy skin, lung lining, intestines and bladder.

Drugs related to vitamin A (retinoids), used to treat severe acne and is still in research to treat certain types of cancer.

VITAMIN D DEFICIENCY

Lack of vitamin A are found in several regions such as Southeast Asia, where rice is milled into rice (which contains little vitamin A) is the staple food.

Some diseases that affect the ability of the intestine to absorb fats and vitamins are soluble in fat, increases the risk of deficiency of vitamin A.
Disease are:
- Celiac disease
- Fibrous cystic
- Blockage of the bile ducts.
Surgery on the intestines or pancreas will also give the same effect.

The first symptoms of vitamin A deficiency is night blindness usually.
Then the precipitation will occur foaming (Bitot spots) in the whites of the eyes (sklera) and the cornea can harden and form scar tissue (xeroftalmia), which can cause permanent blindness.

Malnutrition in childhood right (marasmus and kwashiorkor), often accompanied by xeroftalmia; not because of lack of vitamin A in food, but also because of lack of calories and protein inhibits the transport of vitamin A.
Skin and lining of the lungs, intestines and urinary tract can be hardened.

Vitamin A deficiency also causes inflammation of the skin (dermatitis) and increase the likelihood of infection.

Some people develop anemia.

In vitamin A deficiency, vitamin A levels in the blood decreased to less than 15 mikrogram/100 mL (normal levels 20-50 mikrogram/100 mL).

Vitamin A deficiency is treated with an additional provision of vitamin A as much as 20 times the recommended daily doses for 3 days. Then followed by giving as much as 3 times the recommended daily dose for 1 month.
After it is expected all symptoms were gone.

Patients with symptoms do not disappear within 2 months after treatment, must be evaluated to determine the possibility of malnutrition.

EXCESS VITAMIN A

Excess vitamin A can cause keracunanan, whether it occurs in one-time provision (acute toxicity) or for a long time (chronic poisoning).

Acute Poisoning

Arctic explorers experienced drowsiness, irritability, headache and vomiting within a few hours after eating polar bear liver or heart seals, which contains vitamin A.

Tablets containing vitamin A as much as 20 times the recommended daily dose, which is used to prevent and alleviate skin disease, sometimes cause similar symptoms, even if taken as directed.

Chronic poisoning

Chronic poisoning in children and older adults are usually the result of consuming large doses of vitamin A (10 times the recommended daily dose) for months.
Vitamin A toxicity can occur in infants within a few weeks.

The early symptoms of chronic poisoning are:
- Hair and rough rare
- Loss on the part of the eye lashes
- Lips that are cracked
- Skin dry and rough.

Severe headaches, increased pressure in the brain and general weakness occurs later.

The growth of bone and joint pain often occurs, especially in children.

Liver and lymph nodes may be enlarged.

Babies born to mothers who consume Isotretinoin (artificial vitamin A used to treat skin disorders) during pregnancy can have birth defects.

Vitamin A poisoning diagnosis is established on the basis of 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 added.

Beta-carotene found in vegetables such as carrots, changed slowly by the body to vitamin A and can be consumed in large quantities without causing toxicity.
Although the skin will turn dark yellow (karotenosis), especially the skin on the palms and soles of the feet, but no other side effects.