Do we have to fast Just to feel hunger of poor, well, we can do that without fasting. Good people muslim or no muslim all over world run millions of helping orgs.
No, this is not a valid reason, neither a medical reason nor a training benefit looks good. Nations with no fasting are strong enough without such exercises, in fact more than muslim.
Traveeh or Aitilaf are already proven additions by later muslim clerics.
There are no benefits in fasting except its obedience of a quranic command, you do it, good, dont do it, its not bad. No one will go to hell for not fasting. Any one read that, let us know.