I can think really clearly vs the days that I don't fast and also I would say that my productivity is higher in terms of what I achieve. It has the downside that at 5PM or around I'm already without energy and I stop working compared to normal days when I'm okey up to 11pm.
I also pray 5 times a day as is usual, I'm not sure if that is relevant as afaik it has been found to have similar effects to meditation.
Finally I eat dinner and drink around 9PM