Sofia Ahmed, Muhammad Ali Sheraz, Iqbal Ahmad.
Vitamin A: Nutritional Value and Role in Public Health.
Baqai J Health Sci Jan ;11(2):35-40.

For the past nine decades, research on different aspects on vitamin A (retinol) including nutrition, biochemistry, molecular and cell biology, physiology, toxicology, medical therapy and public health is being conducted all over the world. Vitamin A is an essential micronutrient for all vertebrates. It is required for normal vision, reproduction, embryonic development, cell and tissue differentiation, and immune function in animals and humans. Many aspects of the transport and metabolism of vitamin A, as well as its functions, are well conserved among species. On the other hand, deficiency of vitamin A is also known to be associated with different specific disease conditions such as xerophthalmia, which is manifested as night blindness and corneal abnormalities, softening of the cornea (keratomalacia) and ulceration leading to irreversible blindness along with increased susceptibility to infections and abnormalities in reproduction. Research evidence suggests that diet supplemented with butter, fish, oils, milk and meat could be used as a better source to overcome vitamin A deficiency leading to a healthy life.

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