Vitamin A is one of the vital and essential elements for maintaining many physiological functions of our body.
Vitamin A is fat soluble vitamin. It is found in many natural food sources. There are two types of vitamin – A
1. Vitamin A1(Retinol)- Found in liver oil of marine fish (cod, shark), egg yolk, milk, butter
2. Vitamin A2( Dehydroretinol) – Found in freshwater fishes, carrot, turnip, spinach
Here we are going to discuss the beneficial role of Vitamin A
1. Visualization – Vitamin A plays the most vital role in our visual system. Most of the components which help in visualization are the derivatives of vitamin A. Deficiency of Vitamin A causes the visual problems, causes pathological problems like night blindness and many other serious problems.
2. Epithelial Cell Formations – Vitamin A helps in the formation, differentiation, regeneration and maintenance of normal epithelial cells. It helps in maintaining the healthy skin and hairs. Deficiency of vitamin – A results in many dermatological problems. It also helps in the normal pigmentation.
3. Reproductive Health – Retinol is one of the vital components for maintenance of spermatogenesis and fetal development. Both in male and in female it plays direct and indirect role in reproductive health. It helps to prevent many diseases and make us healthy.
4. Immunity – Deficiency of vitamin A makes us prone to several infections. It is needed for antigen-antibody reactions, proliferation of different immune cells like lymphocytes, natural killer cells, and others. Research found that it is one of the most vital components for all vital immunological reactions.
Excessive Intake of Vitamin A
Excessive Vitamin A causes many pathological problems. Excess retinol is also teratogenic in animals and human. Daily intake should not exceed 20,000 IU. The pathological problems are – biochemical toxicity, nausea, vomiting, dermatitis, exfoliation, hair loss, bone and joint pains, loss of appetite, irritability, bleeding, increased intracranial tension, chronic liver disease.
Deficiency of Vitamin A
Generally this vitamin is stored in liver but in case of long time deprivation cause pathological symptoms to arise like dryness of eyes, spots, softening of cornea, night blindness, corneal opacities, dry and rough skin with papules, hyperkeratinization, atrophy of sweat glands, deficiency of vitamin – A also increases the susceptibility to infection, unhealthy gastrointestinal mucosa, diarrhea. In adults due to deficiency of vitamin A, causes sterility due to faulty spermatogenesis. In females abortions may occur, fetal malformations, growth retardation in children may occur. Vitamin – A deficiency also affect the rod cells more than cones cells as a result visual problems arise, irreversible structural changes with permanent night blindness occurs if the deprivation is long term.