Please don't fast while nursing! You may negatively impact your milk supply.
Both you & babe need a nutrient-dense diet--you need to replenish your nutrient stores & baby is growing.
Eat to hunger & add in organ meats & bone broth if you can.
Honestly you'll probably be fine it you do water fast, but pregnancy and the postpartum period is a time to eat a LOT of nutrient dense food because the developing fetus/baby requires very varied nutrition. Much of that is transferred through breast milk as well.
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