I keep reading that silica is carcinogenic! *double yikes* I'm thinking that something which is sold as an alimentary supplement surely has to be FDA approved and can't be harmful to health, but I would lke to understand the this in theory. Sources say that crystaline silica is the form which is carcinogenic and they also say when inhaled. The silica we take is crystaline if I'm not mistaking. So is it all about how it gets in and where - stomach ok, lungs not ok? Anyone has any knowledge on that?

Ok, just read up on this, and as far as I understand it you get industrial produced silica that they grind to a very very fine dust and the particles, if breathed in, then can be cancerous because they can penetrate through any cell membrane, thus getting past the bodies natural defense system. It said that bigger particles that are in products we use for skin health etc. aren't dangerous because the particles aren't that small and therefore cannot penetrate through cell membranes they shouldn't get into.
We need silica in our bodies and take it in naturally with our food so there shouldn't be really any problems as the supplements generally use silica derived from plants and other natural sources, so should be naturally big.
I hope this helps a little.

Ah, yes I would agree. I understand it's the same with the carcinogenus silica as with asbestos - the tiny fibrous crystaline particles pierce the lung when inhaled and get stuck there where they are impossible to be removed by the body much less physically, thus escaping the body's defense. Ok, I'm appeased now. :)