well I believe its supposed to be around .7g of protein per lb of body weight, thats for women, men being like 1/1. its not too hard to get it if you eat a little for every meal. like for the protein shakes if you use skim milk its something like 8g protein. so a protein shake with milk would be around 30. just get in what you can and I wouldnt recommend going under .5g per lb of body weight, its great for your muscles and its healthy too! now go and drink your water lol