Vitamin A

Contained In

Preformed vitamin A (retinol) comes from animal products such as fish liver oil and beef liver, while Provitamin A (carotene) originates in green, leafy vegetable, apricots, broccoli, cantaloupe, pistachios, parsley, and turnips. Provitamin beta-carotene, once ingested, is converted by the body to vitamin A. Beta-carotene is found in the highest concentration in carrots and sweet potatoes.  Other sources of Vitamin A are eggs, dairy products, and vegetable oils.

Functions*

  • A factor that is important to the eyes and skin.
  • Integral to the formation of blood, strong bones and teeth.
  • Vital to the integrity of the mucous membranes of the nose, mouth, throat, lungs and digestive tract.
  • Necessary for proper protein digestion.
  • Essential for reproduction and embryo development.
  • Required for growth.

*Other essential nutrients also contribute to the physiological functions and processes mentioned here

Dietary Needs DV 5,000 IU

Age

Male

Female

Pregnancy

Lactation

0-6 months*

400 mcg±

400 mcg±

-

-

7-12 months*

500 mcg±

500 mcg±

-

-

1-3 years

300 mcg±

300 mcg±

-

-

4-8 years

400 mcg±

400 mcg±

-

-

9-13 years

600 mcg±

600 mcg±

-

-

14-18 years

900 mcg±

700 mcg±

750 mcg±

1,200 mcg±

19-50 years

900 mcg±

700 mcg±

770 mcg±

1,300 mcg±

51+ years

900 mcg±

700 mcg±

-

-

*Adequate Intake (AI)

±RAE:  1 microgram RAE = 1 mg retinol = 12 mg β-carotene = 24 mg other carotenoids

Toxicity

Age (years)

Upper Limit (IU/day)

Infants-3

2,000

4-8

3,000

9-13

5,667

14-18

9,333

19+

10,000

 

Vitamin A is fat soluble, meaning that the body will not filter out excess amounts. Excess Vitamin A is stored in the liver and can accumulate over time. An intake substantially more than the US RDA can result in hypervitaminosis A, a toxic syndrome. Symptoms include

irritability, vomiting, loss of appetite, headache, dry skin, fatigue, hair loss and mouth lesions.  These symptoms may be the result of any number of other illnesses and do not imply exclusively vitamin A toxicity.

Deficiency                     

Retinol Deficiency (VAD) is rare in the United States, but common in many developing countries. In developing countries, insufficiency is most common nutritional needs are high, such as during infancy, childhood, pregnancy, and lactation. Chronic diarrhea can lead to excessive loss of vitamin A, and vitamin A deficiency itself can lead to further diarrhea.

An early symptom is night blindness, or the inability to see in low light. VAD is one of the top causes of preventable blindness in children. VAD is associated with low iron levels, leading to anemia and with an increased risk of infection.

Best Taken With

Supplemental vitamin A is most effective when the following nutrients are sufficient:

  • B-complex vitamins
  • Vitamin C
  • Vitamin D
  • Vitamin E
  • Calcium
  • Phosphorous
  • Zinc

Additional Data

  • Beta-carotene in the diet may help lead to healthier lives, as reported by the National Academy of Science.
  • Mineral oil increases the absorption of carotene.
  • Some prescription drugs, such as the blood pressure medications, can interfere with vitamin A absorption.
  • Depleted protein levels lead to inadequate vitamin A absorption.
  • Vitamin E facilitates Absorption, storage and utilization of vitamin A.

Products Containing Vitamin A

brought to you by VitaMist, Ltd.

* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure or prevent any disease.
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