In one sense, the only thing that I can think of at the moment that is
not digestable would be cellulose and perhaps lactose in some.  (well, rocks
and
car keys would count too I guess... ;))  The body does a pretty good job
at ripping apart fats, proteins and startches after injesting them,
cellulose
seems to be one of the few chemicals that the body cant 'digest'.  The real
arguements involve macronutrient ratios, food 'poisons' and the like which
prolly have no clear 'simple' answer. Ray Audette's 'naked with a sharp
stick' rule is about as simple a test I've heard and is 'safe' but perhaps
overly cautious.  But what can you do?  My personal belief after alot of
reading,
discussing and wrangling is that you reap most of the benefits of the
Paleolithic
diet by merely being low carb, the rest is gravy.  For some, grains are a
big no-no
but in the majority it prolly doesnt make much of a difference especially if
eating
low carb and really not eating too many grains as part of a daily diet.

There are some that think that allergy testing, pulse testing and muscle
testing are
the way to go but I am very dubious of the results.

  Good luck,

  Wade
carb most times you are eating

>Up until now I've always taken everyones word for it whether certain
>foods are or are not digestible. Assuming that a food isn't digestable
>just because we haven't found any evidence of man eating it before the
>agricultural era isn't really proof. So I started wondering, is there a
>simple test that we can perform to determine whether a food is
>digestible or not? Or do we have to get a lab to determine it for us?
>
>Please, no corn jokes ;)
>
>--Toby