> Because of my fairly severe food allergies, my diet is limited (even
> more than just being paleo) and I have to cook several things in order
> to tolerate them.  Because of this, I sometimes worry about nutrition.
>
Ditto, plus I have malabsorption issues too.  So, paleo or not, I take
hypoallergenic vitamins.


> I know that some vitamins break down or otherwise become useless with
> heat.  Is this effect total?  In other words, will cooking completely
> destroy some vitamins (such that there is _no_ vitamin of that type
> remaining) or does it just reduce it in terms of amount?  Is it the time
> or the heat that determines if it is destroyed?  And, which vitamins are
> susceptible?
>
Rachel and Don could probably handle this question best, but I'll give
it a partial shot.  C, E, folate, and CoQ10 are all affected by heat.  I
don't know if any minerals are affected.  As far as I've read, some C is
retained, but I couldn't guess how much.  I suppose it depends on how
well the food is cooked.  The others--I dunno.  One reference I have
says CoQ10 deteriorates at 115 degrees F. and above. The USDA's standard
reference database,

http://www.nal.usda.gov/fnic/cgi-bin/nut_search.pl

offers values for many foods both cooked and raw.  I'm not sure where I
read it, but A is supposedly more bioavailable with cooking.  I'm also
not sure, however, if they meant carotenes, which are often misleadingly
labeled as vitamin A, or pure vitamin A (retinol). Interesting also is
that riboflavin is destroyed by light, but not by heat.  (You should see
the great time I have cooking and eating my liver in the dark!  Just
kidding :-)

Lois