Not for as far back as I can remember. One of the scarier parts of my childhood was having to hide food so that I could get something to eat on Yom Kippur, and hoping my parents never found out. I do remember at some point being too exhausted to walk either to or from the synagogue even with my father yelling at me - maybe that was when I was young enough to believe enough to actually fast?

I reasonably expect I would do better now, especially if I'd eaten all protein for a couple of days previous - my adult metabolism is not quite as bad as I remember it being in childhood, and my mind is a whole lot stronger. I'm not particularly inclined to test it, though.