Now, that said, I don't do extended fast while breastfeeding (longer than 23 hours). (runholy.com)
Being able to function at a high level, both physically and intellectually, for extended fasting periods was fundamentally important to survival. (idmprogram.com)
Since there isn't a whole lot of info on extended fasting and there is little to no info on it while breastfeeding... I kinda just had to go with my gut! (runholy.com)