‘Fasting’ is not उपवास. उपवास is a super-set of activities , of which ‘Fasting’ is just one aspect, and that too has several aspects based on the season, day of the month and age of उपवासी!
So, whenever I share any benefit of ‘fasting’, remember, it is just benefit of physical aspect of food taken in controlled manner!
उपवास is more than it!! More on it soon