Your body gets the vitamin A it needs through the vitamin A and beta-carotene you consume. It can convert beta-carotene, a substance that gives foods orange, red or yellow color, into vitamin A when you don't consume enough vitamin A to meet your needs. Sufficient intake of these nutrients may prevent or treat cancer, sun sensitivity, osteoarthritis, age-related macular degeneration and oral leukoplakia, according to MedlinePlus and the University of Maryland Medical Center websites.
Vitamin A Recommended Intake
Infants up to 6 months old need 400 micrograms of vitamin A per day, and those between 7 and 12 months old need 500 mcg per day. Children between 1 and 3 years old need 300 mcg per day; between 4 and 8, 400 mcg per day; and between 9 and 13, 600 mcg per day. Females aged 14 and older need 700 mcg per day and males 14 and older need 900 mcg per day. Pregnancy and breastfeeding increase vitamin A needs further, according to the Office of Dietary Supplements.
Beta-Carotene Recommended Intake
Children should eat a variety of fruits and vegetables so they get sufficient beta-carotene from their diet, rather than taking supplements. Adults who want to improve their general health can aim for a beta-carotene intake between 15 and 50 milligrams, with most of the beta carotene coming from food rather than supplements if possible, recommends the University of Maryland Medical Center.
Sources
Foods containing vitamin A include dairy products, egg yolks, fish oils and liver. Fruits and vegetables, including apricots, broccoli, cantaloupe, carrots, mango, papaya, peaches, peppers, squash, spinach, sweet potatoes and tomatoes, contain beta carotene. Both vitamin A and beta carotene supplements are available, with many multivitamins containing a combination of the two sources.
Side Effects and Safety
Vitamin A is a fat-soluble vitamin, so it is stored in the body. High levels are toxic, causing appetite loss, bone pain, diarrhea, dizziness, headaches, irregular menstruation, liver damage, nausea, poor muscle coordination, tiredness, osteoporosis, itching and hair loss. Beta carotene is not normally toxic but can turn the skin yellow if you consume large amounts. Beta-carotene supplements can sometimes cause bruising, joint pain and loose stools.
References
- MedlinePlus: Beta-carotene; Nov. 18, 2010
- University of Maryland Medical Center: Beta-carotene; Steven D. Ehrlich, NMD; Dec. 19, 2008
- American Cancer Society: Vitamin A and Beta Carotene; Feb. 23, 2010
- Linus Pauling Institute: Vitamin A; Jane Higdon, Ph.D., et al.; November 2007
- Office of Dietary Supplements: Vitamin A and Carotenoids
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