Categories: Vitamins

Vitamin A

Vitamin A also known as retinal has several important functions such as, eye normal function, skin normal function.

Vitamin A

Functions Of Vitamin A

helping your body’s natural defence against illness and infection (the immune system) work properly
helping vision in dim light
keeping skin and the lining of some parts of the body, such as the nose, healthy

How much vitamin A needed daily?

The total vitamin A content of a food is usually expressed as micrograms (µg) of retinol equivalents (RE).
The amount of vitamin A adults aged 19 to 64 need is:
• 700 µg a day for men
• 600 µg a day for women

Deficiency of vitamin A

1. Eye: a. Night blindness: impaired dark adaptation. b. Xero-ophthalmia: dryness and roughness of cornea and conjunctiva. 2. Growth retardation. 3. Skin and mucus membranes: a. Roughness of skin (goose skin). b. Roughness of mucus membranes of different body systems e.g. urinary system → infection.

Vitamin a

Excess vitamin A (overdose or hypervitaminosis A)

occurs when excessive vitamin A intake exceeds the capacity of RBP.
Free retinol will release in blood with the following toxic Effects:
Headache, nausea, bone pain and loss of hair.