I have been paleo primal for a couple years - usually (80/20) but I decided to get strict a few weeks ago because the sugar binges were getting way out of hand I was completely addicted to sugar.
So I completely quit sugar on 10/30/12 (even fruit for a while). I eat a huge amount of vegies though and a large sweet potato,
I have noticed when I eat a really fatty piece of meat or something like coconut paleo bread that I just feel wiped out.
I have tested this multiple times since I started and I can tell you for sure that it's the saturated fat.
I remember I used to have the same feeling when I would make bacon then cook scrambled eggs in the bacon grease.
I believe it's saturated fat that is causing the problem because when I cook with olive oil and use plenty of it I don't get the really tired feeling.
I have been thinking maybe I'm not yet fat adapted but I don't think that's it because I can easily skip a couple meals and feel pretty good (even have a little more energy than normal).
A friend who started eating paleo/primal a few months ago says that he thinks that I'm allergic to the saturated fat.
His opinion is that it binds to the intestine wall and blocks nutrients.
Any input would be greatly appreciated - pretty frustrated because fatty foods are what make the NO sugar thing bearable and everyone else seems to be raving about the energy from saturated fats and I'm feeling just the opposite.