One note related to the topic:
"As reported in past posts in archives, I have sometimes eaten eggshells (from organic pastured hens, now from my own EM-fed fre-range hens), often ground first in blender, with no harm. I suspect utility and efficiency depends upon whether your gut produces enough acid to dissolve the shells. Interestingly, Aajonus Vonderplanitz, the founder of Primal Diet, a type of RVAF diet, has stated loudly more than once that he feels that people should not eat ground eggshells, and painted a gory picture of the eggshell pieces acting as pieces of sharp glass in the gut, causing lots of bleeding. However, his opinion and his experience -- which are obviusly true for him at least -- are likely due to the fact that he has written that his gut does not produce hydrochloric acid, due to surgery he had at about age 20. So, this warning may hold true for him, but may not hold true for others.
BTW, as reported in archives, I sometimes dissolve eggshells from my EM-fed free-range hens in EM brew or AEM and ingest the resultant ionic calcium/mineral mix.
with care,
--Vinny"
from
http://health.groups.yahoo.com/group/live-food/message/18344Yuri