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 the health condition caused by prolonged deprivation of 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 preexisting health conditions like gastrointestinal disorders, diarrhoea and protein undernutrition (3).

Functions of Vitamin A

Vitamin A water soluble micronutrient which are 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 have been illustrated below:

  • Inadequate Diet: The most common cause of Vitamin A deficiency across the globe is our diet. We often consume foods which are poor in essential vitamins and minerals such as Vitamin A.
  • Elevated Requirement: Pregnant women requires high doses of vitamin A for the wellbeing of fetus and carrying mother. Deprivation of vitamins during pregnancy may lead to several birth and infant related complications.
  • GI Disorders: Vitamin A deficiency disorders can also be caused by malabsorption. The inadequate absorption of Vitamin A can occur due to 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 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 eyes; It involves drying and thickening of conjunctivae 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 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 blood stream. 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 deficiency like Zinc; in this 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 supervision of doctors. As higher Vitamin A may lead to 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 like 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 agriculture produce.

Prevention of Vitamin A Deficiency

It is often said that “Prevention is better than Cure” and indeed this is very much true with reference to micronutrient deficiencies. Vitamin A deficiency can be prevented through 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.):

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 case of pregnant and lactating women.

Vitamin A is very important fat-soluble vitamin essential for maintenance of healthy visual organs, blood cells 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 adequate amount of Vitamin A as per RDA through various Vitamin A rich diet.