system
Given the following post, respond as if you're commenting on Reddit:
human
If an overweight person and a thin person were both in a car accident which would sustain more bodily damage?
gpt
The amount of energy required to stop each body is linearly proportional to their mass.  So the fat person will take greater energy to stop.

If this is applied through the use of a seatbelt, the force applied to stop them will be applied over a similar area, regardless of their girth.  That is, the seat belt will be exerting a lower pounds per square inch on the skinny dude.

The same argument can be made for heads against windshields (a point collision), legs under the dashboard (again a line).

The only one that is vaguely interesting is the fat guy makes a bigger imprint on the air bag.  But the greater area presented doesn't match his increase in mass, so again he hits the bag with greater force.

Then there is the matter of the health of the individual.  All else being equal, the skinny guy probably exercises more and has greater bone density which can help a lot.