I've done extended water fasting several times. 5-days, 7-days, 10-days, 17-days. It's MUCH easier for me to fast for 7-days than do 7 24-hour fasts. I feel much less hunger and fatigue when doing extended. All the negative experience is in the 1st day or 2 and gets really easy by day 3. So the result is much less net discomfort with extended fasting.