Prohibition of Fasting for a lifetime for the one who will be harmed by that or who will neglect other duties, or does not break his fast on the two 'Ids or during the days of At-Tashriq; It is better to fast alternate days — Sahih Muslim 1159 j

The Messenger of Allah (ﷺ) said to me: I have been informed that you stand for prayer the whole of night and fast during the day. I said: I do that, whereupon he said: If you did that you in fact strained heavily your eyes and made yourself weak. There is a right of your eyes (upon you) and a right of your self (upon you) and a right of your family (upon you). Stand for prayer and sleep. observe fasts and break (them).