Vitamin A

Physiological Effects

Deficiencies of vitamin A has been associated with a number of maladies related to:

• Vision: Retinal is a critical structural component of rhodopsin, the light sensitive (purple vision) pigment within rod and cone cells of the retina.

• Infections: Vitamin A has an anti-infective effect.

• Skin: Epithelial cells require vitamin A for differentiation and maintenance - lack of vitamin A leads to keratinized and scaly skin, due to impaired gene transcription due to insufficient retinoic acid.

• Reproduction: Vitamin A is essentially for the production of sperm and normal female reproductive cycles.

© Image: David E. Volk
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