Thats what many say. You must drink at least 2L a day coz you need to flush those little ketones out!
I drink mine cold from the fridge. If you sip it throughout the day you'd be amazed how much you can get through. Don't forget you can have it in the form of black tea or coffee or peppermint tea.
At the start I struggled to drink 2L a day but now find I am thirsty if I don't have 3.5/4L in a day now!
Hang in there hun, you can do this.
x