Qoute from this http://www.gain-weight-muscle-fast.com/foo...ht-protein.html website:

But isn't there a point where you can really get too much protein?

Probably. And it is probably a point routinely passed by many bodybuilders as they subscribe to the "protein is everything" philosophy. As mentioned, there is evidence consuming in excess of one gram of protein for every pound of bodyweight is optimal (even necessary) for muscle building. However, it doesn't necessarily follow that taking in 3,4 or 5 grams per lb. will be even better.

Taking anything to the extreme is rarely a step in the right direction. Protein is of extreme importance to muscle growth but it is NOT everything. When you take in too much protein at the expense of other nutrients, the body will convert protein to a carbohydrate energy source through a process called gluconeogenisis.

This is not the body's preferred method of acquiring energy. It is not the most efficient method. The conversion takes energy, energy that could otherwise be used to help build muscle.

A balanced diet with sufficient protein intake (1-2 grams of protein per lb. of bodyweight) is the best way to maintain a positive nitrogen balance and build muscle tissue.

If you find yourself to have a fast metabolism that requires you to have a high overall calorie intake in order to gain weight, choosing to have a high ratio of those calories come from protein probably isn't the best course to take. What your fast metabolism (burning an increased amount of calories) is dictating is that you supply it with additional energy (carbohydrates), not protein.

For Example - A person on a 50/30/20 diet at 20x bodyweight would find their diets calling for 2.5 grams of protein per lb. of bodyweight. This is a lot and can present a digestive nightmare.

A wiser course would be to drop the ratio of protein down (opting instead for quality complex carbohydrates) in order to maintain a more reasonable protein intake of 1-2 grams per lb. of bodyweight.