I was a vegetarian for 3 years before that and have been very careful with my diet for all of my adult life. I've cooked most of my meals in the past 15 years and have felt a striking contrast in health since I cut carb out of my diet, including weight loss.
I spend most of my days in an office indeed, as I work in tech. That being said, I've always worked out regularly (especially cardio) and biked to work for the past 7 years. I would say switching to "lifting heavy things" instead of focusing on running probably helped too (though it precedes my paleo diet).
