Vitamin A

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Facts About Vitamin A

What is vitamin A?

“Vitamin A” is the blanket term for retinoids, biologically active compounds that occur naturally in both plant and animal tissues.

The vitamin A that comes from animal sources is fat-soluble, and in the form of retinoic acid, retinal and retinol.

The vitamin A in fruits and vegetables is in the form of  “provitamin A” -vitamin A precursors also known as  carotenoids, which must be converted by the human body into usable retinoids. They are water-soluble and do not accumulate in the body, so toxicity is rare.

Why is vitamin A necessary?

  • Vitamin A plays a vital role in bone growth,reproduction and immune system health
  • It also helps the skin and mucous membranes repel bacteria and viruses more effectively.
  • It is essential to healthy vision, and may slow declining retinal function in people with retinitis pigmentosa

What are the signs of a deficiency?

Vitamin A deficiency is common in developing countries.

  • One of the earliest signs of a deficiency is night blindness. Permanent blindness can result if the deficiency is left unchecked.
  • Vitamin A deficiency also allows opportunistic infectious diseases such as measles and pneumonia to become deadly.

How much need?

  • About 5000IU(adult)
  • About 6000IU(pregnant women)
  • About 8000IU(breast feeding mother)
  • About 2000-4500Iu(1-12years old children)

How do you get enough vitamin A from foods?

  • The richest animal source of retinols is beef liver.
  • The best natural sources of carotenoids are fruits and vegetables, including
  • carrots
  • spinach
  • kale
  • butternut squash
  • cantaloupe
  • mangoes
  • pumpkins and
  • pumpkins and
  • sweet potatoes.

Are there risks associated with too much vitamin A?

Excessive, chronic intake of some forms of vitamin A can be toxic. Avoid taking supplemental vitamin A as retinol or retinoic acid, and instead use plant-derived vitamin A precursors such as beta-carotene (in addition to other mixed carotenoids). Also avoid concentrated animal sources such as cod liver oil (although some forms of cod liver oil are vitamin A reduced and are safe – check the label). Warning symptoms of overdose include hair loss, confusion, liver damage and bone loss.