I was very similar to your situation when starting this about 6 months ago. I had been eating "perfect" according to CW 6 meals a day, lifting heavy, running, all the good stuff.
I stumbled across "Paleo/Primal" because of crossfit, there was a 30 day challenge which promised entirely too many good things for it to be true, but all they asked to prove it was 30 days of strict compliance. I figured I used to eat like crap for 29 years so what harm could 30 days do?
After 30 days I was sold, and never looked back. I haven't been sick since I started. I look, feel, and perform better than I ever have (including when I was in the Army). There are studies to prove or disprove anything you want, but it's pretty hard to argue with personal experience and results you can see and feel for yourself. I decided to trust what my body told me instead of what the government did, and couldn't be happier that I did.