Idk. I never felt miserable or had a burst of energy.

Right now I'm on day 8, and I'm cruising. Of course I've already been in ketosis, so I think my body is trained to switch back and forth between glucose and ketone bodies for fuel. What I love about low carb is that I don't feel as hungry when I'm limiting carbs. Something happens when I eat this way. I don't think about food as much. I miss mealtimes because I'm not feeling hungry so I just forget to eat. And I feel satisfied with less food. It's just weird.

Could be low carb isn't right for you. Or it could be that you need more than 40 grams. Btw, I never count my carbs. I just find it irritating to keep track - measuring and weighing everything I eat.

Ah, measuring and weighing-- that reminds me. There are two other low carb doctors I forgot to mention because most of what they do is in foreign languages. Dr. Annika Dahlqvists and Dr. Jan Kwasniewski. I was attracted to Dr. Kwasniewski's diet because it's so high fat, but it requires fairly rigid fat: protein:carb ratios, and I just will fail at that. He has a couple of books in English but they're hard to get and pricey. Plus, from what I hear he gives contraditory advice at several points.