I don't agree with 2g of protein per body weight first off
for a 200 pound guy it would be 400g.. for a 100 pound girl it would be 200g.. really?
that is a shit ton of meat and what ends up happening is people have to supplement in shakes to even meet that everyday. so they drink 3-4 shakes a day.
what you really should aim for is quality protein. fatty fish, pastured eggs, an occasional grassfed beef are important and full of DHA and vitamins/minerals you need to even function properly.
the 'amount' you need is such bullshit. there isn't a number. lets just say you need protein yes, but the american diet already has a ton of protein. you really should be getting in more green veggies, thats is where we fail at.. if guys started obsessing about getting in 5 servings a day of green veggies, instead of trying to get 500g of protein from shakes.. then i guarantee they would have far better results