Vitamin A deficiency is the major cause of preventable blindness in children and increases the risk of death from severe infections. It is very commonly found in poor countries like African and South-Asian countries. Vitamin A is the most important micronutrient which is commonly known as retinol. It is responsible for maintaining healthy eyesight, cellular differentiation, resistance against infections, epithelial integrity, red blood cell production, and reproduction (1, 2).
What is Vitamin A Deficiency?
Vitamin A deficiency is a health condition caused by prolonged deprivation of a vitamin A-rich diet. It may be caused by inadequate intake of vitamin A-rich diet, elevated requirements in case of pregnancy, and malabsorption due to preexisting health conditions like gastrointestinal disorders, diarrhoea, and protein undernutrition (3).
Functions of Vitamin A
Vitamin A water-soluble micronutrient is present in many food items This hormone is essential for maintaining healthy visual organs, blood cells production and reproduction, cellular differentiation and boosts immunity to keep our body healthy.
Causes of Vitamin A Deficiency
The condition of Vitamin A deficiency can be developed due to various factors. Some of the major cause has been illustrated below:
- Inadequate Diet: The most common cause of Vitamin A deficiency across the globe is our diet. We often consume foods that are poor in essential vitamins and minerals such as Vitamin A.
- Elevated Requirement: Pregnant women require high doses of vitamin A for the wellbeing of the fetus and carrying mother. Deprivation of vitamins during pregnancy may lead to several complications during birth and the infant stage.
- GI Disorders: Vitamin A deficiency disorders can also be caused by malabsorption. The inadequate absorption of Vitamin A can occur due to the presence of preexisting health conditions like gastrointestinal disorders.
Symptoms of Vitamin A Deficiency
The common symptoms of Vitamin A deficiency include (3):
- Lack of rhodopsin
- Dry eyes
- Conjunctiva
- Impaired immunity
- Spot in eyeballs
- Corneal erosion & ulceration,
- Dry skin
- Thickened skin and tongue
Health Risks due to Vitamin A Deficiency
- Nyctalopia (Night Blindness): It is a very rare disease caused by prolonged deprivation of vitamin A. Children and pregnant women are the most vulnerable to vitamin deficiency. Night blindness causes impaired dark adaption of the eyes (2,3).
- Xerophthalmia: It is the primary cause of preventable blindness in children with its earliest manifestations as night blindness and Bitot’s spots. Xerophthalmia is caused by the keratinisation of the eyes; It involves drying and thickening of conjunctiva and corneas (2,3).
- Impaired Immunity: Vitamin A deficiency affects our immunity system. In case of severe deficiency, an individual will get infected repeatedly. The most affected group would be children and the most common childhood infections as diarrhoeal disease and measles (1).
Tests for Vitamin A Deficiency
There are several tests available for the diagnosis of Vitamin A deficiency in our body out of which blood test is the most widely used method of diagnosis. In general, we don’t need to do any preparations for the test but in case you are on Vitamin A supplements you need to stop before the test.
- Serum Retinol Level: Serum for V test for vitamin A measures the concentrations of Vitamin A in our bloodstream. This is the quickest and most accurate test for the identification of retinol deficiency.
- Ocular Diagnosis: Ocular findings like impaired dark adaption and corneal erosion & ulceration may indicate retinol deficiency. However, it may be caused by other deficiencies like Zinc; in these circumstances, rod scotometry and electroretinography helps in ascertain vitamin A deficiency.
Remedies of Vitamin A Deficiency
- Vitamin A Supplements: If you are diagnosed with severe Vitamin A deficiency, you should consider medical supplements under the supervision of doctors. As higher Vitamin A may lead to a deadly health condition.
- Vitamin A Rich Diet: Vitamin A-rich food items will help in minimising the Vitamin A deficiency. Some of the Vitamin A-rich food items are organ meat, cod liver oil, dairy, fish, egg yolk, carrots, spinach, sweet potatoes, dairy products, green leafy vegetables, papaya, oranges, pumpkin, broccoli.
- Fortified Food Items: Several agricultural lands across the globe are poor in micronutrients which will serve nutrient-deficient food produces. Fortified seeds will help in providing nutrient-rich agricultural produce.
Prevention of Vitamin A Deficiency
It is often said that “Prevention is better than Cure” and indeed this is very much true about micronutrient deficiencies. Vitamin A deficiency can be prevented through the consumption of Vitamin A rich diet.
Food items rich in Vitamin A:
- Organ meat
- Cod liver oil
- Milk
- Dairy Products
- Fish
- Egg yolk
- Carrots
- Spinach
- Sweet potatoes
- Green leafy vegetables
- Papaya
- Oranges
- Pumpkin
- Broccoli
Adequate Intake (>19 yrs.):
A simple way to prevent Vitamin A deficiencies is to maintain recommended daily intakes. The recommended daily intake of Vitamin A for an adult is 700-900 mcg. However, it may be higher in the case of pregnant and lactating women.
Summary
Vitamin A is a very important fat-soluble vitamin essential for the maintenance of healthy visual organs, blood cell production and reproduction, cellular differentiation, and immunity. It prevents night blindness and xerophthalmia in children and pregnant women.
Although Vitamin A deficiency has several ill effects, it can be treated with the right consultation and medical supplements as prescribed by medical experts. The best possible way to avoid these complications by consuming an adequate amount of Vitamin A as per RDA through various Vitamin A-rich diets.