The events observed in the beta-carotene experiment ("Cancer Prevention," Hot Papers, The Scientist, 12[10]:11, May 11, 1998) were interesting but not unexpected. While the beta-carotene and vitamin A were given at a good dosage (30 mg beta-carotene and 25,000 IU of vitamin A), there is no indication that any of the other vitamins were supplied to the subjects. It's likely that they only had the trivial amounts specified in the RDA. The choice of dosage for their study was probably based on mouse data. However, mice produce about two to four grams (based on a 70 kg man) per day of vitamin C, which is probably essential to the anticancer activity of the beta-carotene and vitamin A. I'll bet if the human subjects had been given three to five grams per day of vitamin C, the results would have been different and favorable.
The fact that mice and rats (and ...
