Vitamin A - Supplements Tablets Capsules

Essential for

healthy eyes and vision
growth, repair and cell differentiation
health of epithelial cells
protection against infection
a healthy reproductive system

Absorption and metabolism

Fat is necessary for vitamin A absorption.

Deficiency

Symptoms include night blindness, xerophthalmia, dry skin, retarded growth, increased susceptibility to infection and cancer.

Sources

Good sources of pre-formed vitamin A include liver, butter, whole milk and egg yolks.

Daily recommended dietary intakes

Men                        1000 mcg RE (3333 IU)

Women                  800 mcg RE (2666 IU)

Pregnancy             800 mcg RE (2666 IU)

Lactation                +500 mcg RE (1666 IU)

1 mcg RE is equivalent to 3.33 International Units (IU).

Toxic effects of excess intake

Symptoms include headaches; bone and joint pain; dry, itchy skin; and liver damage. High daily doses of vitamin A (above 3000 mcg RE) in pregnancy may cause birth deformities.

Interactions

Mineral oil laxatives, cholestyramine, colchicine and alcohol decrease vitamin A absorption.

Therapeutic uses of supplements

Supplements are used to boost immunity; prevent cancer; treat skin disorders such as acne and psoriasis; and treat eye problems.

Cautions

Supplements should not be taken with vitamin A-derivative acne drugs or broad spectrum antibiotics. Pregnant women should avoid doses of vitamin A above 3000 mcg RE.

Vitamin A Categories:

Vitamin A
Vitamin A Health
Vitamin A Absorption
Vitamin A Deficiency
Vitamin A Sources
Vitamin A Recommended Daily
Vitamin A Overdose
Vitamin A Interactions
Vitamin A Dangerous

Other Vitamins:

Vitamin A
Carotenes
Beta carotene
Lycopene
Lutein
Thiamin
Riboflavin
Niacin
Vitamin B6
Folate
Vitamin B12
Biotin
Pantothenic acid
Vitamin C
Vitamin D
Vitamin E
Vitamin K