#VitaminA #Blindness #VitaminsSeries
What is vitamin A?
Vitamin A is a fat soluble organic compound required for vision and for epithelial tissue health. It is converted in the body from dietary beta-carotene and 3 other carotenoids. 80-90% of vitamin A is stored in liver.
Vitamin A is also called retinol.
What is vitamin A deficiency?
The normal range of vitamin A/retinol is 28–86 μg/dL. Vitamin A deficiency is defined as serum retinol levels of below 28 μg/dL. Vitamin A deficiency can lead to blindness, skin disease and growth retardation in children.
What causes vitamin A deficiency?
Primary vitamin A deficiency is caused by prolonged dietary deprivation.
Secondary vitamin A deficiency is caused by reduced absorption, storage or transport of vitamin A.
What are the signs and symptoms of vitamin A deficiency?
Vitamin A deficiency is the leading cause of preventable blindness in children worldwide.
Impaired dark adaptation (night blindness) due to lack of the photoreceptor pigment rhodopsin.
Xerophthalmia: dry, thickened conjunctiva and cornea
Bitot spots: keratinized growths (metaplasia) on the conjunctivae causing hazy vision
Keratomalacia: corneal erosions and ulceration
Vitamin A deficiency can also be recognised by its keratinising effect on the skin and mucous membranes.
Dry, scaly, thickened skin with prominent follicular scale
Dry lips and thickened tongue
Keratinisation of the urinary, gastrointestinal and respiratory tracts
Other symptoms and signs
Impaired immunity leading to gastrointestinal and respiratory tract infections
Growth retardation in children
Vitamin A deficiency can be prevented through a diet which includes:
Spinach, kale, collards, brocolli and other leafy green vegetables
Beta-carotene-rich fruits such as apricots or peaches, and highly-coloured vegetables such as carrots, squash, sweet potato
Milk or cereals that have been fortified with vitamin A
Liver
Egg yolks
Fish liver oils
Refrence:
