I work in software, and I've seen far too many guys in my industry who are either skinny as a rail and surviving on Cheetos dust, or painfully overweight. Had several co-workers croak unexpectedly, at shockingly young ages.
It's a real problem in the industry. People simply plop themselves down at their computers and forget to do anything else for an entire day.
I have kids, and refuse to let them lose their dad early, so I hit the gym for an hour in the mornings, at least every other day. I do a mix of cardio and weight training. I also never stay seated for longer than 45 minutes.
Seriously, guys... If you work in the software industry, make a habit of getting up and moving around. It doesn't actually take much to reap enormous benefits just from staying more active.