[TanyaRD]

I don't know of any randomized human trials that have been able to definitively determine that vitamin c did not interfere with chemo. I would be very interested in seeing these trials. I search PubMed and could not find anything. Unfortunately, it is a very difficult thing to prove in human trials because there are so many other factors that can interfere. For instance, people with the "same" cancer diagnosis receiving the same treatment can have very different response rates. If a patient taking vitamin C had a worse response than a patient not taking vitamin C one might conclude that it was the vitamin C that caused the poor response but there is no way to determine if that patient would have responded poorly despite the vitamin C. In human studies the factors of genetics, diet, activity, socioeconomic status and others all interfere. I don't know what form of vitamin C Heanly used in his studies. It is an interesting point.