How much additional weight can a human endure on their bodies before dying?

For example if the person is a female, 5'5, 125lbs, in her 20's and the weight is distributed evenly over her upper torso while in an upright position. As if she were wearing one of those protective suits they make you wear when you take an x-ray at the dentist, only heavier. How much weight could be endured in this situation to make the person (a) uncomfortable, (b) in pain, and (c) die. 100lbs, 200lbs, 250lbs? You tell me. ------- Obviously I know it would depend a little from person to person and perhaps with training, muscle mass etc, etc, I simply would a ball park figure -------- Thank you. :)