I have this problem and will mindlessly eat anything in arm's reach while working. I used to buy mints for anyone passing by to have, but would eat them myself... and they would go fast. I put on about 10kg before I realised that it was because I was essentially eating a bag of sugar every day...
For a couple of weeks my wife bought me chocolate-coated coffee beans once a week. These lasted about 5min once I remembered about them at work, due to (a) yumminess, (b) tendency just to mindlessly eat at the desk.
After that, because chocolate-coated coffee beans are expensive, I figured I'd cut out the middleman and I bought a 5kg bag of coffee beans and just munched my way through that.
DO NOT DO THIS, even though it sounds cool.
After a couple of hours the increased caffeine made me jittery, my heart rate was up, my head hurt and my skin was dry and scratchy.
After a few weeks I quit that. It was hard. I'm a water addict now.
