I work in North OC ... takes me 10 minutes to get in the office---no freeways, no road rage, very little stress. The actual stress begins when I get to work.
OTOH, I have relatives that commuted from Fontana/Riverside area to Westwood and Rosemead ... everyday for over 15 years. They have health problems as described in the report ... but I don't know if it's due to the commute, work hours, job stress, boss stress, domestic stress, financial stress, genetics, poor diet, lack of exercise ... or all the above.
I'm sure the "obesity in america" study follows the same trends.