> Thinness is not an issue, since sugar is not off limits.

Paleo eating excludes refined sugars completely, and asks you to reduce fruit. Meat and veg, nuts and seeds, some fruit, no grains, no dairy.

> A week won't do it on the diet change,

Totally agree here. And switching from a traditional high-carb, low-fat diet to paleo leads to 2 or 3 weeks of feeling like crap. We're 5 weeks into our Paleo Challenge at the gym I own, and most people are feeling like a million bucks. We do our best to impress upon them that the first 2-3 weeks will be difficult.