I think it depends on your metabolism. It suits some people but fasting does bad things to both my blood sugar levels and my temper. :)

For me the key has been to give up eating snacks of any kind. I just sticking to 3 meals a day. Re sugar, I avoid added sugar, in things like tea or cereals and I don't eat many biscuits or cakes, but I don't worry about hidden sugar any more. I try to cook from scratch, so a bit of sugar in baked beans or a sauce isn't going to do much harm.