I would say drink normal or decrease. Some people do "dry fasts" which means no food AND no water. I've seen people do dry fasts for as long as two weeks and there's a Russian doctor (can't think of the name of the top of my head) that cures a lot of ailments with it.
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This is the place: https://medica-tour.com/diseases/fasting-lake-baikal
I read a lot about them, some friends even were there to cure their "untreatable" illnesses. Really magical thing is fasting.
I too have heard stories of long fasting, but never "dry" ones, wow.