An interesting article from the University of Sydney about our need for protein. If a person is not getting protein in, they will eat more. Fortunately, most weight loss surgery patients focus on protein first.
I know that when I do not get enough protein in my diet I feel like I can't stop eating it is like my body is craving something it just can't find. Also, I have learned the hard way that if you do not get enough protein in your diet you can retain water and end up with edema in your lower extremeties...I had to go on a prescription water pill and lost 6 pounds of water weight.