Low carb/low fat will work, I am on a plan called Ideal Protein that is that way. Bulk of my calories are protein, but it is still a very low calorie diet, and keeps hunger and cravings at bay. That being said, you can do this in a paleo/primal way (that plan is NOT, except dinnertime), and yes you will lose weight fast.
Yes, I know which forum I'm on, looking forward to ditching packets for primal after I drop 10 more lb.
Lol, edited to add. I was just replying to OP, apparently there are 27 pages of posts!