recent study in Australia shows that having a desk job will increase your chances of developing a tumor in your bowels by 94 percent. Apparently even vigorous exercise won't help:
"Even a high level of vigorous recreational physical activity did not
modify the effect of sedentary work.' And they warned: ‘The findings
have occupational health implications, given that advances in technology
have led to increasing amounts of sedentary behaviour at work.' Sitting
down on the job is thought to lead to increased blood sugar levels and
damage insulin production, both of which have been linked with the
development of bowel cancer"
So basically you're screwed.