When fasting might as well add the juice of a bunch of lemons, also I would consider helping the kidneys with some kidney tea.
One of my favorites is Celery Seed Tea for 4 or 5 days. 1 Tablp. of Celery seeds ground in a coffee grinder, add 2 cups of boiling water and sip throughout the day, maybe add lemon juice and a little stevia. Success, Giz.