Weight / Fat loss

One bit of good advice I read was to have a protein shake in the morning, which should keep you feeling full through most of the day. Then balanced meals.

From memory (and i read this years ago) your muscles can only operate on glycogen (form of carbohydrate) and although your body can convert protein to be used as fuel it's not very efficient.

Yeah. So if you don't eat enough carbs your body will start breaking down your muscle, so you'll actually loose muscle density.

So you take protein after training to stop your body breaking down muscle first, and then afterward to help build muscle