Have you seen the old ladies and men, going on fast, even today?Those who are old, now in their eighties and nineties, even today, fast on specific days, including full moon days. There was, and is, a particular logic behind the fasting. They would go on fast, possibly to help digest the food or toxins that go into our body.
Members, who are doctors by profession, will be able to explain the scientific reasoning. However, what needs to be understood is that there was, in those days, an economic reason too. They, our parents, belonged to a different generation. The salaries were low, and inflation was quite high. They even possibly saved a little money here and there.
That kind of sacrifice is now history. Or is it? Do you still see them fasting? What can we learn from them?