Ketosis is a fairly dramatic change in your body's physiology - the normal biochemistry every medical student learns - glycosis - doesn't happen. I would say there can't have been enough studies on that to be sure one way or another. I don't think anyone here or anywhere can give you a scientific answer but I would try to not be in ketosis while nursing. But if you feel fine and aren't loosing weight, I can't imagine you are in ketosis!

I believe SBD recommends phase 2 when you are pregnant or nursing and for teenagers, not phase 1. Thats what I would do to be safe - you can't possibly be wrong if you do phase 2 and drink enough! You must feel like a horse because I remember drinking like crazy when nursing (I nursed 2 kids, 1 year each), and I drink a lot on the diet - especially like now when I want to get out of a stall! If you keep drinking and good carbs and good fats, you should be fine.