I have been in the gym for 37 years. I know. Old. I only know that because I wrote the date down on my weight belt, which I still use, in1981. 1981 and OSHC which stood for old school hard core. I trained back then with allot of guys that had amazing builds and knew from experience and from talking to older gym members.
Back then, before all the fitness magazines and websites, you looked at guys that had the build you wanted and asked them for advice. What works, what doesn't, ect. Not the steroid guys who could do anything and grow but the real lifters.
Paleo is a fad. It was popular in '65, again in '79 and '89. If anyone wants to argue with me about that I have two questions: How long have you done it and is it sustainable? Two, what is it based on? I know the theology. Human diet went wrong when we became farmers. Wheat whatever. My question is why would Neolithic man start farming a grain, food, ect. that he wasn't already eating? Not a single scientist will tell you what Paleo man ate. Mostly anything he could find. But he certainly did not start farming an unknown grain just to see what it was like in his diet.
Eat in moderation. It comes down to calories (units of energy) and calories out. Burn more than you take in. Calorie is a unit of measurement not a physical thing.
I once challenged a friend of mine, a UCSD nutritionist. I said I could eat nothing for a month but snickers bars and tortilla chips and drink nothing but Diet Pepsi and beer and still be 9% bodyfat and ripped. I won.