nutritional disorders
Vitamin A Deficiency
Etiology ofVitamin ADeficiency
Primaryvitamin Adeficiencyis usually caused by Prolonged dietary deprivation It is endemic in areas such as southern and eastern Asia, where rice, devoid of beta-carotene, is the staple food. Xerophthalmia due to primary deficiency is a common cause of blindness among young children in countries with high rates of food insecurity. Secondaryvitamin Adeficiencymay be due to Decreased bioavailability of provitamin A carotenoids Interference with absorption, storage, or transport ofvitamin A Interference with absorption or storage is likely in Celiac Disease , 