Feeding Dogs Human Food

Hello,

My mother in law feeds her dog everything from the table. She goes as far as to make him his own plate of whatever they are eating for dinner and sometimes even hand feeding him from the plate(very disturbing).

The little guy is getting kind of fat and has trouble breathing. She loves the dog very much and doesn't seem to notice she is slowly killing it.

Is human food really that bad for dogs? Does everyone feed their dogs fatty, greasy food? How do break it to her that she could be setting it up for a heart attack?

-Jeff