Have you read anything by Dietrich Klinghardt on this topic?
I don't know if it is true, but the claim made is that candida will tie up heavy metals. Many people on the heavy metal chelation forum report increased candida when chelating and then a subsequent overall improvement once a few rounds of chelation are completed.
I think it would be very interesting if someone somewhere would actually confirm this scientifically and measure heavy metals containined in candida.
Anyway, I am inclined to believe more than not believe as when you look to nature the function of fungus is always to clean things up. In the Humanure handbook written by Joe Jenkins he provides some citations for the recduction of heavy metals by certain soil organisms - there are hunreds of thousands of these oganisms probably more.
So I tend to think of candida as nature's best solution to cleaning up people's guts. Don't get me wrong, I know it is horrible to actually be a human composte bin, but nature just does what it does without regard for people's suffering.