Hope some of these suggestions help. Like AliCat says its trying to find non food related things. Being at work just makes it more challenging.
Carry some happy music on a phone, mp3 player etc when start getting stressed pop in an earphone. I used to have one earphone in all day when worked in shared office . Listening to audio lectures etc.
Avoid excessive caffine. Its a neurotoxin that jangles your nerves.
Small book/kindle/droid tablet. If things get tough pop to toilet. Put seat down and sit and have 5 mins reading. Mumbling 'dodgy takeaway' stops all questions.
Am lucky as a technician I can pick up any generic computer part or peripheral and go for a short walk. Often see other people walking notepads or letters. Clipboards are the tops though
Make sure to vary your path regular for good counter surveillance.
Simple meditation techniques like making a happy place. Creating imaginary coloured energy balls etc. I like simple darkness techniques. Find a really dark place and spend a while there just relaxing and getting a sense of it. Next time you feel stressed recall the feeling of darkness. If you can make it work it likes getting a comforting hug. Kind of tricks your body into that relaxed pre sleep state. There's hundreds on net.
Or if want practical try researching 'memory palaces'. See how far can push the limits of what you can remember. Build a virtual world of knowledge in your head.
Bit more fun? Try positive thinking manifestation. Imagine something unusual that could happen but be specific. More probable, clearer and more defined the event the better. Like wouldn't it be fun if some one came in the office with a red balloon? Then just wait for it to happen. lol, who knows? Seems to be popular pass time on net at moment
People thinking of money and getting rich then finding notes, coins etc.. Am currently waiting for Geri Halliwell to bring me a cuppa
gotta aim big lol.
There is the Mindfulness thing. The whole Zen chopping wood , carrying water. Just focussing on the task you are doing without your mind making up stories about it or attaching meaning to it that impacts on your sense of identity. Great for nipping stress in the bud but hard to master.
Am learning the old style Calligraphy so can turn my post it notes into mini works of art
With the big fancy Capital letter at the start.
Hope you have fun and good luck with the weight loss.