I'm going to have to disagree with the theory that it doesn't matter where your sources of macronutrients come from.
As far as carbs are concerned you should really steer clear of gluten, wheat, legumes and grains. That stuff can really mess up your gut, and as you know your gut is your 2nd brain, so if you're eating a lot of stuff that's going to mess up your intestinal track and your belly you're going to feel like sh*t.
As far as protein is concerned I would go with some good clean whey, grass fed beef or some wild caught salmon. Don't fuck with that corn fed beef, because it will really mess up your innards.
I would get my carbs from things like nuts, greens and non-starchy veggies like yams and sweet potatoes.
Google the "Paleo diet" or "Paleolithic diet" and you'll see what I mean.