mice eat grains, they are designed to do so. humans are not. dr. christopher failed at this point, because he lived in a dry desert area where sweet fruits are not natural, but with irrigation grains were grown.
my favorite author used grains to build muscles, his true education was to eat only the most alkaline grains and chew them to a liquid in the mouth before swallowing, our saliva can work on such foods, but since they are not fruits of the tree, our body struggles with them.