Junk food at office

I saw an advertisement on the televison, about a lady eating pani puri and the vendor advising her about the ill effects of junk food. About improper digestion, burping etc etc.

So, I was wondering, after moving to new campus, I have easy access to Junk Food every evening. though I eat only once / twice a week (which is tooo much), I had an idea of intaking fibre by having Oats or Cornflakes? I hope I do not end up with an upset stomach.

What say??