Fasting and nursing

I have a nine month old that refuses to eat solids so therefore I'm pretty much still nursing exclusively! I concerned about fasting (no liquids or solids) for 18 hours for the next 28 days I will be consuming food around 3 am and again when I break my fast each day roughly around 9:30! I try and consume as many liquids and eat as much as possible as I cam in these few short hours I am wondering how this will affect my milk supply ?

Note from the lactation consultant:
There is no way to predict how your supply will be effected. It could have little impact on supply as long as you are meeting a minimum of 1800 calories per day. But if you go below 1800 calories it could surely effect your supply. Baby will simply want to nurse more frequently to catch up on supply.

Liz Pevytoe, RN, IBCLC