Vitamin A is found in several forms in
dietary supplements. Preformed vitamin A (vitamin A acetate and vitamin A palmitate) has well-recognized toxicity when consumed at levels of 25,000 International Units (IU) per day, or higher. (Beta-carotene does not have the potential for adverse effects that the other forms of vitamin A do, because high intakes of beta-carotene are converted to vitamin A in the body at much lower levels). The RDA for vitamin A is 1,000 retinol equivalents (RE) for men, which is equivalent to 3,300 IU of preformed vitamin A, and 80 percent of these amounts for women.
The adverse effects associated with consumption of vitamin A at 25,000+ IU include severe
liver injury (including cirrhosis), bone and cartilage pathologies, elevated intracranial pressure, and
birth defects in infants whose mothers consumed vitamin A during pregnancy. Groups especially vulnerable to vitamin A toxicity are children, pregnant women, and those with liver disease caused by a variety of factors, including
alcohol, viral
hepatitis, and severe protein-energy malnutrition.
There are some studies that suggest vitamin A toxicity has occurred at levels of ingestion below 25,000 IU. In addition, the severity of the injuries that occur at 25,000 IU suggests that substantial, but less severe and less readily recognized, injuries probably occur at somewhat lower intakes. Most experts recommend that vitamin A intake not exceed 10,000 IU for most adults or 8,000 IU for pregnant and nursing women.
See your doctor if you have experienced serious side effects associated with Vitamin A supplements. In addition, it may be important to
contact an attorney who can help you protect your legal rights. Please keep in mind that there may be
time limits within which you must commence suit.
See Also
- Vitamins: Overview
- Birth Defects
- Broken Bones: Overview
- Hip Joint: Overview
- Liver Problems