Like Mickey and BellyDruid said, vegetarian lifestyle is impossible without supplements, and I believe that if what you are eating isn't satisfying you body's needs no matter how much you eat of it, then you need to change your diet.
Also like Mickey said, the extra protien in meat is conducive to higher brain function, in fact most researchers today beleive that man kind as a whole would never have developed language without that extra protien nurishing the brain.
16 years