Question: why is vitamin a deficiency common in developing countries

title: Vitamin A deficiency
text: The major cause is roughage which include few animal sources of pre-formed vitamin A . In addition to dietary problems , there are other causes of VAD . Iron deficiency can affect vitamin A uptake . Excess alcohol consumption can deplete vitamin A , and a stressed liver may be more susceptible to vitamin A toxicity . People who consume large amounts of alcohol should seek medical advice before taking vitamin A supplements . In general , people should also seek medical advice before taking vitamin A supplements if they have any condition associated with fat malabsorption such as pancreatitis , cystic fibrosis , tropical sprue and biliary obstruction . Other causes of Vitamin A deficiency are inadequate intake , fat malabsorption , or liver disorders . Deficiency impairs immunity and hematopoiesis and causes rashes and typical ocular effects ( e.g. , xerophthalmia , night blindness ) . 

Answer: answer: The major cause is roughage which include few animal sources of pre-formed vitamin A.
Other causes of Vitamin A deficiency are inadequate intake, fat malabsorption, or liver disorders.
answer: The major cause is roughage which include few animal sources of pre-formed vitamin A.  Iron deficiency can affect vitamin A uptake and excess alcohol consumption can deplete vitamin A.  Other causes of Vitamin A deficiency are inadequate intake, fat malabsorption, or liver disorders.