That's baloney, and you defended it with an irrelevant demurral about racemization, which involves molecules which are NOT structurally identical.
You then presumed to send me to school, but unfortunately, your own post is also factually incorrect. D-amino acids are not universally toxic; neither are L-sugars. L-gulose and L-fructose occur in nature and the studies confirm they are effectively metabolized.
Review your biochemistry.
My response was to the tone of your post, which was that of a pompous ass.