What it does in the body
Vitamin A is necessary for proper vision, resistance to infectious diseases, epithelial cell integrity, bone remodeling and sperm reproduction. Vitamin A deficiency usually results from malnutrition, but can also be due to abnormalities in intestinal absorption of retinol or carotenoids. Deficiency is prevalent in humans, especially children in certain underdeveloped countries.1
Food Sources
- Vitamin A can be found in liver (beef, pork, chicken, turkey, fish), carrots, broccoli leaves, sweet potatoes, kale, butter, spinach, pumpkin, collard greens, cantaloupe, eggs, apricot, mango and winter squash.2
Recommended Dietary Allowance
- The RDA for vitamin A ranges from 600 micrograms (2,000 IU) to 900 micrograms (3,000 IU), but for lactating women can be as high as 1300 micrograms (4,333 IU). Excessive vitamin A (as retinol) may be harmful during pregnancy. However, pregnant women may very safely supplement with the beta-carotene form of vitamin A.
Orthomolecular Dosage Range: Somewhat higher than the RDAs; orthomolecular physicians prescribe much higher amounts during some illnesses.
Vitamin A is known as the anti-infective vitamin because it maintains healthy mucous in the respiratory system and thus fights off infection and allergic symptoms.
For many years Reich (1971) treated patients with asthma with a combination of vitamin A, vitamin D-3, plus bone meal to supply calcium. Reich’s doses of vitamin A range from 28,000 to 75,000 I.U. per day, while doses of vitamin D range from 5,000 to 14,000 I.U. daily. On a very large series of 5,000 cases, the results have been favourable.3
1 http://www.vivo.colostate.edu/hbooks/pathphys/misc_topics/vitamina.html
2 Vitamin A (Retinol). Site viewed December 9, 2007. http://www.vivo.colostate.edu/hbooks/pathphys/misc_topics/vitamina.html
3 Hoffer, Abram, PH.D., M.D. and Walker, Morton, D.P.M. Orthomolecular Nutrition: New Lifestyle for Super Good Health. Keats Publishing Inc., Connecticut: 1978. Pg. 132 – 133.