A buddy of mine is doing this. Got his mom and wife on it now too.

He lost weight is now lean and more energetic than ever. His mom's auto-immune disease (don't remember which) hasn't given her any of her flare ups as of late.

At around the 2-week mark of the diet gave him dizzy spells and some gut issue. It lasted 2 days and only came back when he decided to have some sugary cocktails.

I think the most apparent sour ce of benefit has been from the elimination of processed foods and other junks, including alcohol. However, I'm skeptical about the long-term damage that this kind of diet could do without too many studies including mortality data.

Some of the most interesting stuff that I've seen about the diet is about the unexpectedly low (bad) cholesterol. Something about the elimination offsets the effects of all those eggs and meat.