The Food and Drug Administration (FDA) has recommended a daily allowance of 5000 IU of vitamin A. Vitamin A deficiency is a common phenomenon occurring in underdeveloped and developing countries, however, rarely seen in developed countries, and even if it does occur, it occurs in the case of alcoholics.
Such a deficiency can be conduced by inadequate intake of vitamin A-containing foods, liver disorders, and fat malabsorption (due to diseases such as cystic fibrosis, cholestasis, celiac disease). In the early 1900s, infants in Denmark were observed to be stricken by this deficiency. The reason behind this was the absence of milk fat from the milk. Milk suppliers were skimming the milk and using the fat to make butter, leaving the milk void of fat, which surprisingly resulted in this deficiency.
Prolonged dietary deprivation, as observed in Southern and Eastern Asia, wherein, polished rice that is the staple food is low in beta carotene, thus, results in xerophthalmia (eyes failing to produce tears). This is the common cause of blindness in children dwelling in developing countries. Besides malnutrition, another cause is defective storage and circulation of vitamin A in the body.
Symptoms of Vitamin A Deficiency
The different symptoms of vitamin A deficiency are as follows.
- Corneal inflammation
- Night blindness
- Poor vision
- Skin rash
- Lack of appetite and vigor
- Defective teeth and gums
- Retarded growth in children
- Dry and dull hair
- Rough and dry skin
- Excessive hair loss
- Ridged nails
- Poor wound healing
- Poor sense of taste and smell
- Weakened immune system
- Prolonged and frequent common colds
- Formation of small, white spots in the inner eyelids
- Vulnerability to urinary and respiratory tract infections
- Keratinization (accumulation of keratin) of the skin
- Skin disorders: pimples, boils, premature wrinkles, and acne
- Mucus formation ability of the body is hampered
Keratinization of the eyes results in xerophthalmia, which is a condition in which the tear glands of the eyes stop producing tears. Hence, the conjunctiva and cornea of the eye dry up, and become thick and wrinkled. If left untreated it can result in corneal ulceration and ultimately blindness. Night blindness can even lead to complete blindness if left untreated.
Vitamin A deficiency can be diagnosed with the help of blood tests. Once diagnosed, the patient will be asked to follow a diet with foods containing vitamin A. Treatment involves intake of vitamin supplements. Pregnant women should take such vitamin supplements only under medical supervision. In general, the supplements need to be administered under the guidance of a medical practitioner, or else there are chances the deficiency can develop into a case of toxicity. Thus, intake of the right amount of vitamin A has to be maintained.
Disclaimer: This article is for informative purposes only and does not in any way attempt to replace the advice offered by a medical expert.