Updated December 20, 2022
Food & Supplements Program
“Vitamin A” is actually a family of molecules that are involved in most forms of life. Plants and bacteria make beta-carotene and related molecules; animals eat beta-carotene, where it is converted by the liver to several forms of Vitamin A (retinoids).
Vitamin A Units Changing
10,000 IU = 3000 mcg = 3 mg
This information is for educational purposes only, to facilitate quality conversations between patients and their personal physician(s). Several additional considerations are required to safely administer any protocol for an individual. This information is NOT intended to diagnose, treat or encourage self-treatment of any medical condition.
Vitamin A Factoids
- Many people cannot adequately convert beta-carotene to vitamin A.
- There are conventional blood tests for Vitamin A and “Retinyl Binding Globulin.
- The concern about Vitamin A toxicity (“someone once died from eating a bear liver”) is overblown and is similar to the past concerns about Vitamin D. Most of us are deficient in many vitamins and minerals including Vitamin A. Holistic authors believe that doses of 20 – 40,000 IU are safe (and possibly essential) for most people, while doses up to 200,000 IU can be used short-term.
- The fat-soluble vitamins A, D, E and K often co-exist (such as in the liver) and are co-dependent
- Vitamin A deficiency affects night vision.
- Vitamin A deficiency in Africa is a major cause of irreversible blindness in children.
- Vitamin A deficiency has been linked to cervical dysplasia in women.
- Vitamin A is involved in gut health.
- Vitamin A is necessary for immune system defense against viruses.
- Vitamin A deficiency can look like excess especially with skin and hair.
- Vitamin A is essential for proper thyroid function.
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