In the beginning of Atkins I have noticed that I get EXTREMELY tired and seriously have cravings for the sugar. It is almost as bad and trying to fight off the cravings for cigarettes (I have quit.) When you are over the cravings and the lethargy goes away it is incredibly noticable. I wake up with the alarm and have not one time of wanting to go back to sleep (extremely unusual for me since I take Paxil.) I have also notice a different kind of "full" feeling. It is higher up in the stomach, just under the ribcage unlike the "full" feeling where you want to bust.

A question, however. I have heard that if you feel lightheaded when you are on Atkins it is possible that you are losing too fast...I really don't know about that. I get lightheaded but I don't lose alot. I just love the "ALIVE" feeling and the clarity of mind that comes when your body has detoxed....

Any comments?

I know I had a similar feeling, I felt kinda of tired for a week, just a muscle tiredness like I'd worked out for a long time. Then in week 2, BAM. Waking up at the butt crack of dawn full of energy.
I don't wake up at dawn anymore, that not being my natural state, but I still have lots of energy, and I've noticed that when the alarm goes off, I am ready to get up (unless like last night, when I had a vodka gimlet and I sure could have used a few more hours...)
The lightheadedness could be a lack of potassium (try adding some more meat and/or avocado to your diet if you don't want to take supplements) or it could be the ketones working, Dr. Atkin's book said it could have that effect on some people.

I get the lightheaded feelings too, was much worse when I started, then when the energy hit me like a brick wall, I forgot about it. It comes back every once in a while, but I just happen to be tracking what I think is the link for me. Hidden sugar. Not sure and havent got enough information gathered yet, but the last three times it has happened, there have been foods that I had eaten about an hour before that could have had hidden sugar carbs... just my theory.
Or could just be the ketones????