Beta Carotene (and other Carotenoids)
Description:
Carotenoids are a group of pigments that are foundnaturally in
dark green, red and yellow fat-soluble compounds. Over 600 different
carotenoids have been identified, with 30-50 having provitamin A
activity. Alpha, gamma, and beta carotenes are converted primarily in
the intestinal mucosa to vitamin A (retinol). Approximately 33% of
beta carotene from food gets absorbed and only 33% of the absorbed
beta carotene is converted to retinol.
Supplement Forms:
- Alpha and beta carotene from the algae Dunaliella
- Palm oil - best form
- Synthetic - all are trans beta carotene
Labs:
- Plasma Beta Carotene - 50 - 250 mcg. / dl.
Provitamin A Carotenoid Food Sources:
- Dark green leafy vegetables - spinach, green peppers,
collards, etc.
- Fruits - apricots, papayas, lemons, oranges, watermelons,
apples, peaches
- Red vegetables - red peppers, tomatoes
- Yellow vegetables - corn, squash, sweet potatoes, carrots
Nonprovitamin A Carotenoid Food Sources:
- Crustaceans
- Fruits
- Trout
- Vegetables - spinach, green and red peppers, green plants,
carrots, corn, potatoes, mushrooms
Causes of Deficiency:
- Cholecystitis
- Cholelithiasis
- Dietary insufficiency
- Liver diseases
- Pancreatic diseases
Adverse Reactions and Toxicity:
- Elevated carotenoid levels in the blood do not lead to vitamin
A toxicity
- High amounts of carotenoids may produce hypercarotenemia and
reversible yellow discoloration of the skin
Drug/Nutrient Interaction:
- Protein deficiency may impair the conversion of provitamin A
carotenes to vitamin A
- Thyroid hormone deficiency may impair the conversion of
provitamin A carotenes to vitamin A
- Vitamin C deficiency may impair the conversion of provitamin A
carotenes to vitamin A
- Zinc deficiency may impair the conversion of provitamin A
carotenes to vitamin A
Biochemical Functions:
- Antioxidant
- Cellular screen against sunlight induced free radical
damage
- Due to antioxidant effect, protects arteries and inhibits
damage to cholesterol
- Increases all T cells
- Increases helper/inducer T cells
- Increases white blood cell function and number
- May be helpful in cancers involving epithelial tissues - i.e.
uterus, vagina, cervix, lung, skin, gastrointestinal tract
Clinical Indications:
Copyright 1998 - 2008 by L. Vicky Crouse, ND and James S. Reiley, ND. All rights reserved (ISSN 1527-0661).