Apologies for repeating myself, but Doug Ginsberg wrote:

>Does anyone know if traditional food preparation techniques such as
>soaking, sprouting, and fermenting  are effective responses to some of
>these plant toxicity issues...

Whole meal cereals and other seeds have in their shells phytic acid which
is not toxic but strongly binds to minerals like calcium, iron, zinc and
magnesium to form insoluble salts, phytates. There is overwhelming evidence
that whole meal cereals through this mechanism decrease the absorption of
such minerals to a point where cereals are no longer an optimal human food.
Phytates are most certainly an important contributing cause of iron
deficiency in third world countries and possibly in the western world. As
to calcium deficiency the picture is less clear.

Mellanby found back in the 30s that puppies got rickets when they were fed
oats. The possible absence of rickets in preagricultural skeletons, its
apparent increase during medieval urbanization and its epidemic explosion
during industrialism can hardly be explained only in terms of decreasing
exposure to sunlight and descreased length of breast-feeding. An additional
possible cause is a secular trend of increasing inhibition of calcium
absorption by phytate from cereals since these apparently increased in
amount during the Middle Ages, and since old methods of reducing the
phytate content such as dampening and heat treatment may have been lost
during the emergence of large-scale cereal processing. Old fashion
sourdough baking as well as soaking and fermenting decrease the amount of
phytatic acid by use of phytases, enzymes which are also found in the
cereals but which often are destroyed during industrial processing.

>...and were any of them used by paleolithic
>hunter-gatherers?

I don't think there is any evidence of that. I suppose they would need
pottery which they apparently did not use.

Staffan