The molecular structure of diatomaceous Earth is such that the sharp edges of the molecules cut the parasites. DE does not dry out the bugs or parasites... Slices and destroys them.
No, the property of killing insects is from drying them out. Check Web MD. I did present accurate information.
Actually, it does work by dehydrating the insects:
“Diatomaceous earth causes insects to dry out and die by absorbing the oils and fats from the cuticle of the insect’s exoskeleton. Its sharp edges are abrasive, speeding up the process.”
http://npic.orst.edu/factsheets/degen.html
It’s great stuff. I used it to keep bugs out until we could get the damaged door from garage to basement fixed. Those big wood cockroaches never made it more than a couple of feet.
Not sure it’s a good idea to eat it, but small amount probably won’t hurt you. Try not to breathe in in.