| Life Extension Foundation's Preliminary |
Rebuttal to a Recent Vitamin C Study
April 9, 1998
HIGH DOSES OF VITAMIN C CAUSE DAMAGE
On April 8, 1998, British scientists released the results of a study showing that vitamin C was effective for cancer prevention and free radical suppression at the dose of 60 mg a day, but at 500 mg a day, it caused genetic damage that could lead to cancer or rheumatoid arthritis.
The researchers gave 30 human volunteers 500 mg vitamin C supplements for six weeks. The scientists showed that while 500 mg a day produces protective effects, it also appears to have a dual activity in which it can also cause damage.
Higher doses of vitamin C were shown to react with iron and other metals to damage cellular DNA.
This small study help to validate The Life Extension Foundation's 17-year position that vitamin C must be taken with other antioxidants like vitamin E, or the vitamin C will react with iron and copper to produce DNA-damaging free radicals.
Saul Kent, President of The Life Extension Foundation, first brought out this information in 1978, when he cited animal studies showing that high doses of vitamin C, given without other antioxidants, actually shortened the life span.
Most vitamin supplement users consume at least 400 iu of vitamin E, and 400 mcg of folic acid every day. The addition of these two nutrients could have prevented the iron-induced DNA damage observed by the British scientists. More specific antioxidants like n-acetyl-cysteine, grape-seed and green tea extract would provide significant protection against DNA damage induced as a result of vitamin C catalyzing with iron and copper.
The British scientists did note that even at the high dose of 500 mg of vitamin C a day, it was preventing more damage than it was creating.