Can you be so fat that it will stop a bullet?
If the said bullet was being shot at you from a projectile
triggered weapon, aka a gun, then no, no amount of fat will shield
you from a bullet travelling at a hightened speed via it's
projection and fire based propellent as a gun.
Yet if someone threw a bullet at you, or more preferably, your
stomach, the misplacement of firepower and speed will render the
bullet pointless, thus not peircing your skin, i.e. 'hitting' you
in terms of a gun.
So if your going to imitate the matrix whilst carrying an extra
bit of weight round the middle, then make sure your cardboard
cutouts of the agents don't use guns.